Goodnight Sweetheart

An unusual Britcom whose premise is that a down-on-his-luck TV repairman in a failing marriage (Gary Sparrow, played by Only Fools and Horses' Nicholas Lyndhurst) finds he has the power to travel through time to the 1940s. Once there, he meets a young woman and they fall in love. And now suddenly there's no need to go through the trauma of a divorce in the 1990s, because he can have two separate lives...

Gary gets away with it by having his best friend Ron, a printer, print him easily-forged 1940s white banknotes to fund his past lifestyle, and justifies his knowledge of the future events of WW 2 to Phoebe (his past wife) by claiming to be a secret agent. Eventually Gary ends up running a 1940s memorabilia shop built over the time portal, whose merchandise, while genuine, is suspiciously well preserved.

Came fiftieth in Britains Best Sitcom.

Tropes used in Goodnight Sweetheart include:

Actor Allusion: In one episode someone props up the bar access behind Gary and he almost leans on the empty space, but then notices and nods to himself—this provokes gales of uproarious laughter from the audience, which will seem a strange non sequitur to anyone not familiar with the famous scene in Only Fools and Horses in which Del Boy (not Lyndhurst's character Rodney, oddly) does the same but goes crashing to the floor with a fixed expression.
Fake Brit: Irish actress Dervla Kirwan as Phoebe.
Flanderization: Compare the portrayal of Reg Dedman in the pilot with what he would become by series 2. He essentially transforms from a dopey yet competent constable into a man who is an older and thinner version of Chief Wiggum.
Hey, It's That Guy!: One of Nicholas Lyndhurst's many, many attempts to get away from everyone thinking of him as Rodney from Only Fools and Horses
Ho Yay: In the episode where Gary ends up accidentally splitting himself/cloning himself. The final Gary, "Good Gary", is gay, and starts to hit on Ron. If these are parts of Gary, you have to wonder what this implies about him.
Identical Grandson: Reg Dedman.
Jack the Ripper: Appears in one episode where Gary accidentally time-travels the wrong way. Turns out his mysterious disappearance was because he, too, was a time traveller, and got run over in modern London.
Knife-Throwing Act: Part of the entertainment troupe in "How I Won the War".
A Little Something We Call "Rock and Roll": Gary, a pianist, would play songs from the future and claim he had written them himself. One of the show's cleverer aspects was that they were sometimes arranged in a more contemporary style, such as a jazz version of California Dreamin'.
The Load: Arguably, Yvonne. Gary clearly wasn't happy in the 90's to begin with and most of his problems stem from trying to juggle his life with her and his life with Phoebe. One could argue that the fact Gary keeps going back to the past is a clear indication that its the only place he actually is happy in and all his problems stem from his time-period.
- Its also worth noting that apart from Ron, we never see Gary engage with any other friends in his present. Compare that with the numerous relationships he forges in the 40's, definitely signifies a lot about where Gary would rather be.
No Celebrities Were Harmed: Averted, many famous characters appear in the 1940s segments...but of course none of them are around to complain about their portrayal. In later series, Noel Coward was a recurring character and Clement Attlee appears in the final episode.
- Also Robert Maxwell, and George Fornby.
The Other Darrin: Both of the actresses playing Gary's two wives were replaced over the show's run.
Politically-Correct History: Subverted hard and uncomfortably in the episode The Yanks are Coming. Two black American soldiers find themselves the victim of racism via a Southern American Sergeant. Also notable in the kind but surprised reactions of Phoebe and Reg who had never seen black men in the East End before.
Portal Slam: Gary finds himself trapped in 1945 in the final episode.
Real Song Theme Tune: "Goodnight Sweetheart" was a popular 1940s song by Guy Lombardo.
San Dimas Time / Meanwhile in the Future: Rarely used but occasionally crop up, for example in the last episode where Gary's message to the future appears as he writes it in the past.
Shout-Out: In one episode Gary ends up meeting the Resistance in Occupied France, who are represented by a woman who dresses like Michelle from Allo Allo and uses her Catch Phrase "Listen very carefully, I vill say zis only wurnce".
- An episode with a bank manger called ~~Mainwearing~~ Mainwaring and a chief clerk named Wilson who act identically to the characters of the same name in Dad's Army.
The Slow Path: Hinted at in a couple of episodes. Used by Gary a few times to send messages to himself in the future.
Time Travelers Are Spies: Gary gets mistaken for a spy in an early episode. He manages to convince his captors that he's a British spy.
Too Dumb to Live and Cloudcuckoolander: Reg Dedman..
World War Two