Directed by Cast Member

"Leonard Nimoy: Melllvar, you have to respect your actors. When I directed Star Trek IV the Voyage Home, I got a magnificent performance out of Bill because I respected him so much.

William Shatner: And when I directed Star Trek V the Final Frontier, I got a magnificent performance out of me because I respected me so much."

- Futurama

Later on in an ongoing TV series run, one of the cast members may get the idea in their head to take a turn at the helm. They'll have been around a set and crew for some time now and having shifted from the floating jobbing actor life to a more stable schedule, a desire to try something new may be piquing up. Now considering that by this stage they will have a decent relationship with the production staff, who probably don't want to say no and who also don't want the stars to getting ideas of wandering off into their head, the idea of directing an episode will come up.

Not much will change stylistically in this episode, since a good budding director will try to emulate the ongoing style to fit it while a bad one would hopefully be steered heavily by the established staff, however the episodes may be noted for sticking the actor's character out of the way so that they can focus on the directing. On the other hand, maybe they go for the opposite, having an episode that does focus heavily on them, so that they don't so much have to deal with directing other people's acting.

Of course, you might not want to trust the coffee passed to you by the guy who went to film school, worked as a runner for five years and spent every day sucking up to the director to no avail...

Writer-actor, director-actor and other hyphenated jobs titles are normally used to refer to someone who develops more than one role simultaneously. That is not this trope. This trope is about those whose careers evolve (or attempt to evolve) into another role, using their current employment as a springboard. Think Dual classing vs Multi-classing with Directed by Cast Member being Dual Classing.

Anime

 * Liam O'Brien, Gaara's voice actor, works on Naruto as a writer and, on other projects, moved on to voice director.
 * Caitlin Glass directed Ouran High School Host Club and also voiced Haruhi.
 * Cast members directing is fairly common across the board in dubs by FUNimation.
 * Its fairly common across the board in dubs period. Anime Dubbing doesn't pay a lot, so a lot of voice actors pull double jobs in the industry. Well-known examples would be Amanda Winn-Lee, Stephanie Sheh, Wendee Lee and many others.

Films

 * Clint Eastwood started doing this in the 70's.
 * In fact, the Director's Guild of America has a rule named after Eastwood. It prevents a current cast or crew member from replacing the director of the film (it became the Eastwood rule after Clint gave the boot to Philip Kaufman when shooting The Outlaw Josey Wales). This is why, in a Troubled Production like Rambo First Blood Part II or Tombstone where the director quits or gets fired, the de-facto cast member director has to find a de-jure director to work through.
 * Let's not forget he was recognized as the oldest man to direct his own film and have it become a #1 box office hit with Gran Torino
 * Woody Allen, obviously
 * Several of the Star Trek films.
 * Kurt Russell ghost directed some scenes of Tombstone after the original director was fired. After a new director was found, Russell still helped with some of the directing.
 * Russell has said that he ghost-directed the entire film, with George Cosmatos taking credit so it didn't look like Russell forced his way into the director's chair. The only condition was that Cosmatos would take credit until he died (which happened in 2005).
 * Cosmatos is also supposed to have become the director for the film for the reason that he did the same during First Blood Part 2 (as mentioned above).
 * Jack Nicholson has officially directed 3 films (he helped co direct the Roger Corman production The Terror) including Drive He Said for the same studio that did Five Easy Pieces, a western called Goin' South and the Chinatown sequel The Two Jakes. This makes for an odd filmography of mostly less than well received star vehicles.
 * In The Dark Knight, Heath Ledger directed the handheld videos shot by the Joker.
 * In a case of What Could Have Been, a candidate for directing the third Harry Potter film was Kenneth Branagh, who had played Professor Lockhart in the previous film. In the end, however, Alfonso Cuaron was chosen as director.

Live-Action TV

 * Mash's Alan Alda.
 * Harry Morgan and Mike Farrell also directed several episodes each. David Ogden Stiers directed a couple. Even Jamie Farr had one episode behind the camera.
 * Friends - David Schwimmer, who parlayed this into a career directing feature films and TV shows in which he does not star (most notably Run Fatboy Run).
 * Stargate SG 1 - Christopher Judge wrote several episodes and Michael Shanks directed several and wrote a few (interestingly, one of Shanks' early episodes involved robot clones and he was able to get out of half of the screen time by just killing the clone).
 * Amanda Tapping directed an episode (season 7's "Resurrection", which, incidentally, was written by Michael Shanks).
 * Ben Browder also co-wrote an episode.
 * Robert Carlyle also directed an episode of Spin-Off Stargate Universe.
 * Ben Browder wrote two episodes of his earlier series, Farscape: Green Eyed Monster and John Quixote.
 * Sanctuary - Amanda Tapping has taken more than one spin in the director's chair, while Robin Dunne made his directing debut in season 4.
 * The West Wing - Richard Schiff, the episodes "Talking Points" and "A Good Day".
 * Tom Welling got seven episodes (one each in seasons 5, 6, 7, 8 and 9, and two in season 10) on Smallville. The first one was considered to be one of his character's better episodes.
 * Michael Rosenbaum, John Schneider and Justin Heartly all directed one episode each (in seasons 6, 3 and 10, respectively), while Allison Mack directed two (one each in seasons 8 and 9). Heartly also got to write one episode of season 10.
 * About 3/4 of the entire cast of all five Star Trek series have directed at least one episode. William Shatner has directed one of the movies, and Leonard Nimoy and Jonathan Frakes have each directed two of them.
 * Gates McFadden, who is more well regarded as a choreographer than actor, directed the episode "Genesis," where her expertise in directing movement was put to good use. Her own character spends most of the episode in stasis, freeing her to focus on direction.
 * Star Trek also passed along cast member directors between series. Roxann Dawson and Robert Duncan McNeill both directed episodes of Enterprise, and Dawson also directed episodes of Voyager. Jonathan Frakes directed an episode of Deep Space Nine. Levar Burton tops them all by directing episodes of Star Trek the Next Generation, Deep Space Nine, Voyager and Enterprise.
 * Star Trek Deep Space Nine was so fond of this that even Andrew Robinson (a recurring guest star, rather than a main cast member) directed an episode.
 * Note that many of the Star Trek cast member-directors are now or were professors of directing and acting for the stage: Jonathan Frakes (Rockport College), Avery Brooks (Rutgers University), Andrew J. Robinson (USC), Rene Auberjonois (Juilliard).
 * While normally the episodes directed by a cast member either don't feature their character or only feature them briefly, the much-praised Deep Space Nine episode "Far Beyond the Stars" sticks out because it was directed by Avery Brooks, who features prominently in pretty much every single scene.
 * The reason for this was that the episode was about racism in the 1950s and the writers thought that the episode would suffer if it wasn't directed by someone who has to live with it today.
 * The episode was originally supposed to star Cirroc Lofton, but it had to be changed due to schedule issues.
 * One of the complaints Garrett Wang had about his time on Voyager was that he never got to a direct an episode, despite asking several times. In fact, Wang holds the dubious distinction of being the only actor in the entire franchise who wanted to direct, but was never allowed to. Looks like Harry Kim's Butt Monkey status is contagious...
 * Scrubs has seven episodes directed by Zach Braff (who, at the point he started directing episodes, had already written and directed one movie), including "My No Good Reason", "My Princess" and "My Way Home" ("My Way Home" even being one of the most well-received episodes of the later years of the show's run). Bill Lawrence has said Braff is probably the best director in the crew for large-scale shoots, which is why the more unusual episodes often go to him.
 * David Boreanaz directed a fifth-season episode of Angel in the episode where Angel spends all his time bedridden in hallucinations.
 * He also directed a fourth-season episode and the 100th episode of Bones.
 * Robin Williams directed the final episode of Mork and Mindy.
 * Peter Falk directed an early episode of Columbo and also wrote one of the post-1989 episodes.
 * In addition, regular guest star Patrick McGoohan directed a number of episodes.
 * Edward James Olmos has directed three episodes of the new Battlestar Galactica Reimagined. He also directed the 2009 BSG TV movie, The Plan.
 * The Bob Newhart Show - Peter Bonerz started directing episodes in Season 2, beginning a successful career behind the camera on this and many other series.
 * Susan Flannery has been a regular director on The Bold And The Beautiful in addition to her starring role as Stephanie Forrester for several years now. Her directing skills so impressed CBS that she was invited to direct a few episodes of another soap on CBS, Guiding Light.
 * The Brady Bunch - Robert Reed
 * Zachary Levi directed a major third-season episode of his TV series, Chuck vs. the Beard.
 * Coach - Craig T. Nelson
 * Several members of the production team of British Game Show Countdown are former contestants of the show.
 * Dalziel and Pascoe. Both Warren Clarke (Dalziel) and Colin Buchanan (Pascoe) directed episodes.
 * The Dick Van Dyke Show - Jerry Paris went on to a long directorial career on this and many other shows.
 * The Drake and Josh episode "Battle of Panthatar" was directed by Josh Peck.
 * Drake Bell got his turn by directing the first part of the "Really Big Shrimp" special
 * Kelsey Grammer has directed numerous episodes of Frasier, many focusing on his character although his first episode, "Moon Dance", only featured Frasier in 2 scenes. Dan Butler (Bulldog) has also directed an episode, albeit one in which his character does not appear.
 * Several of Grammer's episodes are ones with notable flourishes: "Three Valentines" involved one continuous take as Niles sets his trousers on fire, as well as three independent storylines; "RDWRER", which is set mostly in a Winnebago; "Rooms With A View", which is set in a hospital waiting room with flashbacks being done by transitions to other rooms; and in "Don Juan in Hell: Part 2", Frasier ends up in a cabin full of guest stars every girl he's ever dated (including his mother, as he always was a Freudian).
 * Unsurprisingly, several episodes of Hawaii Five-O were directed by Jack Lord.
 * Adrian Paul directed several episodes of Highlander the Series.
 * Hugh Beaumont directed a number of Leave It to Beaver episodes.
 * Paul Schrier (Bulk) directed several episodes of Mighty Morphin Power Rangers with Jason Narvy (Skull) assistance, much to many people's surprise given the morons they played. Reportedly they were offered the opportunity to make up for many of their scenes in The Movie being cut.
 * The Monkees: Micky Dolenz and Peter Tork directed episodes. Dolenz later had some success as a TV director in Britain.
 * Night Court - John Larroquette helmed a couple of episodes.
 * Patrick McGoohan always had complete control over The Prisoner, so it isn't surprising that he wrote and directed many episodes - usually under pseudonyms.
 * Michael Chiklis (Vic Mackey) has directed a few episdoes of The Shield.
 * Dick Christie directed a few episodes of Small Wonder.
 * Parodied in a sketch by The State: An actress is starring in and directing a TV costume drama. The scene shown is a monologue of hers, which is repeatedly injected with camera instructions.
 * WKRP in Cincinnati: Frank Bonner directed 5 episodes, and Howard Hesseman and Gordon Jump directed one each.
 * David Duchovny directed a few of the later episodes of The X-Files, namely "The Unnatural" (also wrote it), "William", and "Hollywood A.D." (he also wrote it), and he also had a few co-writer credits for other episodes.
 * And Gillian Anderson directed "All Things," which further explored her character.
 * Carroll O'Connor directed episodes of Archie Bunker's Place and In the Heat of the Night.
 * Colin Ferguson (Carter), Joe Morton (Henry), and Salli Richardson-Whitfield (Allison) have all directed episodes of Eureka.
 * Jason Bateman directed Afternoon Delight of Arrested Development. The episode is "standard fair" (as in, a show with a large ensemble where the majority of the characters gets a subplot each).
 * The Mary Tyler Moore Show: One episode directed by Mary herself.
 * CHiPs: episodes directed by Robert Pine and Larry Wilcox
 * The Incredible Hulk: several episodes directed by Bill Bixby, plus two directed by Jack Colvin ("Goodbye Eddie Cain" and "East Winds").
 * The FBI: Nine episodes between 1970-74 directed by Philip Abbott.
 * Diagnosis Murder: One episode is directed by Barry Van Dyke.
 * Dragnet: All episodes of the 1950's and 1960's versions directed by Jack Webb.
 * The Rookies: Two episodes directed by Georg Stanford Brown ("Cliffy" and "Someone Who Cares") and one by Gerald S. O'Loughlin ("A Time to Mourn").
 * The Streets Of San Francisco: One episode directed by Michael Douglas ("Spooks For Sale").
 * Kojak: several episodes directed by Telly Savalas.
 * Starsky and Hutch: Both Paul Michael Glaser and David Soul have directed episodes (though unlike Glaser, Soul never pursued it further).
 * Miami Vice: Both Don Johnson and Edward James Olmos have directed episodes.
 * Randolph Mantooth directed 2 episodes of Emergency. His character spent one of them in the hospital after being hit by a car in The Teaser, but he still had a lot of screen time. Kevin Tighe directed several episodes, writing another, and Michael Norell wrote 4.
 * The Office (US): To date, Paul Lieberstein has directed five episodes, while Steve Carrell and B.J. Novak have directed two apiece and John Krasinski, Rainn Wilson, and Mindy Kaling have each helmed one.
 * Neil Patrick Harris directed an episode of How I Met Your Mother.
 * Hugh Laurie directed the "Lockdown" episode of House, a Bottle Episode involving a (you guessed it) lockdown which neatly sticks characters in pairs in a single set for the entire episode, rotating through the pairs. So Laurie is free to be behind the camera for most of the episode and when he's in front of it it's in a tight character focused box.
 * As if sweeping Best Actor Emmy awards wasn't enough to take up Bryan Cranston's time, he also directed the second and third season premieres of Breaking Bad.
 * Over 30 episodes of Married With Children were directed by Amanda Bearse (Marcy), who directed numerous other shows as well.
 * Here's a strange one: Dennis Dugan was brought in for 4 episodes near the end of Moonlighting, where he played the infamous "guy Maddie met on a train and immediately married for no apparent reason in order to provide a love triangle". This failed utterly and his character was written out and never seen again. However, Dugan himself stuck around to direct 5 unrelated episodes (and now Dugan is probably better known as a director than an actor).
 * This trope itself was parodied in the 'Shakespeare' episode of Moonlighting. In one scene, 'Petruchio' (David Addison) pulls out a list of demands for Kate (Maddy Hayes). He reads out 'Top billing, 10% pay rise and a chance to direct' and then says 'oops wrong list of demands'.
 * Matthew Gray Gubler (Dr. Spencer Reid) directed three episodes of Criminal Minds:
 * "Mosley Lane" (5x16): This one was definitely a Tear Jerker episodes and, especially considering it involved heavy acting with teenagers and young children, was incredibly well executed. When you're able to get multiple really good performances out of kids, you're doing something right.
 * "Lauren" (6x18): This one was Paget Brewster's (Emily Prentiss) "goodbye episode" and she wanted Matthew to direct it. Another fantastic episode which involved . Needless to say, it was a Tear Jerker.
 * "Heathridge Manor" (7x19): Very intriguing episode which was described by Matthew as "eerily cerebral". This one was more about the psychological horror rather than the blood and guts.
 * On another note, directing is actually Matthew's passion.
 * Mad Men has two season-4 episodes directed by John Slattery (who plays Roger Sterling).
 * This allows for some pretty cool visual irony: the opening scene of Slattery's first episode involves Sterling and Don Draper discussing new regulations on cigarette advertisements over the phone with Lucky Strike; one of these requirements, as Sterling reads out, is avoiding using wide angles, low and other forms of Hitler Cam to make a smoker seem superhuman. At the same time, Don Draper is smoking, and Slattery makes sure to use...wide angles, low shots, and other forms of Hitler Cam to make Don seem...well...you know the rest.
 * Lots of Mystery Science Theater 3000 episodes, though this likely has to do with the show being produced in Minnesota, away from major show business cities.
 * Homicide:Life on The Street had multiple episodes directed by Clark Johnson who later directed episodes of The Shield and The Wire as well as feature films. Kyle Secor also directed one episode. Steve Buscemi, who appeared in a guest role in Season 3, got to direct at least one later episode, in which he did not appear.
 * Shannen Doherty directed three episodes of Charmed, including the last one she ever appeared in.
 * Ryan Stiles directed an episode of The Drew Carey Show. Humorously, The Tag at the end of the episode featured the cast members congratulating him before they shoot the final scene, in which the camera ends up zooming in on Ryan and only focusing on him while the other characters marvel at some wonderous shape-shifting object offscreen.
 * Jensen Ackles directed the sixth season episode "Weekend at Bobby's" and the seventh season episode "The Girl Next Door" of Supernatural.
 * Patricia Wettig and Polly Draper are just about the only stars of Thirtysomething who didn't direct an episode; one episode even featured Elliot (Timothy Busfield) making his directorial debut on a commercial.
 * Jennifer Love Hewitt helmed three episodes of Ghost Whisperer.
 * Jennifer Garner directed one episode of Alias in season four.
 * Tom Wopat, James Best, Sorrell Booke and Denver Pyle all directed multiple episodes of The Dukes of Hazzard (Uncle Jesse did the most, with 12); John Schneider only directed one, but it was the Series Finale and he also co-wrote it (Schneider was the show's only cast member to write an episode).
 * Scott Bakula directed three episodes of Quantum Leap. Notably, he averted the trope in Star Trek Enterprise. (Reportedly, he was asked due to his previous experience, but he opted not to.)
 * Thirty Rock star Tina Fey has written and co-written several episodes, including the Pilot, but she has never directed any. Steve Buscemi, who has a Recurring Character on the show, directed an episode in which his character did not appear.
 * Trackdown. I Spy. The Greatest American Hero. What do these TV series have in common? They all starred Robert Culp, and he wrote and directed episodes for each of them. This was a factor in his not being cast as Koenig on Space:1999; he told Gerry Anderson that he wanted to write and direct, and was handed his hat as a result. In fact, the only cast member of any live-action Anderson show to have directed an episode is Robert Vaughn, who went behind the camera for The Protectors's only comic episode "It Could Be Practically Anywhere On The Island" (widely regarded, including by Vaughn himself, as a mistake).
 * Happens in-universe in Extras when the network hires an incompetent director for the Show Within a Show.
 * Danny DeVito directed three episodes of Taxi.
 * Bruce Campbell who played Autolycus in Xena: Warrior Princess and Hercules: The Legendary Journeys directed episodes of both series including the Series Finale of the latter.
 * Malcolm Jamal-Warner directed several episodes of The Cosby Show.
 * Home Improvement: Tim Allen and Patricia Richardson each directed one episode in season eight.
 * David DeLuise, who plays the father on Wizards of Waverly Place, directed a number of episodes, one or two of which were written by TV son David Henrie.
 * Boy Meets World: William Russ (Alan Matthews) directed several episodes in the later seasons.
 * Jon Cryer directed three episodes of Two and A Half Men.
 * Matthew Morrison directed the Glee episode "Extraordinary Merry Christmas"
 * Phill Lewis (Mr. Moseby) of The Suite Life of Zack and Cody and its spinoff The Suite Life On Deck directed one episode of the original show and eight On Deck episodes (as well as episodes of ANT Farm and Jessie).
 * James Roday has directed several episodes of Psych and has actually earned co-producer status of the series.
 * Notably, he's the go-to director for most of the show's horror parody episodes, such as "Tuesday the 17th", "This Episode Sucks", and "Heeeere's Lassie".
 * 19 episodes of St. Elsewhere were directed by Eric Laneuville (aka Luther Hawkins).
 * Not to mention the episodes directed by David Morse (Dr. Morrison) and William Daniels (Dr. Craig).
 * ER had episodes directed by Laura Innes (12 total), Paul McCrane (9), and Anthony Edwards (4). Laura Innes and Paul McCrane even directed episodes after leaving the cast.
 * Grey's Anatomy - Chandra Wilson (6 episodes) and Kevin McKidd (2 episodes).
 * Chad Lowe has directed two episodes of Pretty Little Liars so far (appropriately enough given he plays Aria's dad, the second episode he helmed was called "Father Knows Best").

Music Videos

 * John Flansburgh directed a couple of videos for They Might Be Giants songs.
 * "Weird Al" Yankovic directed a number of his own (and others') videos.
 * Dave Grohl directed the videos for several Foo Fighters songs, including "Rope" and "All My Life."
 * After everyone's dissatisfaction with the video to "One Step Closer", Linkin Park's Joe Hahn has been responsible for almost all of their videos.
 * Jerry Casale of Devo directed or co-directed the majority of their videos, as well as their short film The Truth About De-Evolution and their "video albums" The Men Who Make the Music and We're All Devo. He also co-directed "Army Girls Gone Wild" by his own side project Jihad Jerry And The Evil-Doers, and directed the segment of the film Human Highway in which Devo are performing "Worried Man".
 * Adam Jones of Tool is responsible for their music videos.