Torchwood/Recap/S1 E3 Ghost Machine

We join our team In Medias Res as they chase down a fleeing suspect. Tosh is certain the miscreant is the source of the alien reading they're receiving. Unfortunately, Gwen only gets so far as retrieving his hoodie. Fortunately, there's an object in his pocket which is in fact the source of the alien reading. Gwen finds the device and activates it. Through the device, she sees a vision of a young boy dressed in period clothes wandering through the train station.

From the train tag Gwen saw on the boy, Torchwood is able to track him down to his current status: as an old gentleman living in Cardiff. He was left alone after having been evacuated from London when he was just a boy during World War Two. Turns out the alien device is a "quantum transducer", a device that allows the user to see events spurred by strong emotion. The scene Gwen saw was brought on by the immense fear he felt at being alone.

Deciding the device is dangerous, Torchwood sets out finding the original suspect they were chasing to learn where he got it. Returning to the scene, this time Owen uses the device and sees a vision of the 1960s, where a young woman, Lizzie Lewis is raped and murdered by a suitor getting a little too rough with her. Owen feels her incredible fear and despair -- a bit of a shock for him, seeing as he drugged and raped a woman and her boyfriend just two episodes ago -- and decides to bring her murderer to justice. Despite the rest of the team claiming that the case has gone cold and no good will come of this investigation, Owen tracks down the murderer, Ed Morgan. Understandably, Mr. Morgan has no interest in discussing the incident.

During this investigation, Owen finally corners their original suspect, one Sean Harris. Sean tells Owen and the rest of Torchwood that he saw the vision of Lizzie and Ed also. He says he got the device from inside a tin he stole from an old lady, which turns out to be full of benign alien stuff that fell from the Rift. He also offers Torchwood "the second half" of the device. They put the device back together and Gwen activates it, seeing herself nearly hysterical with blood covering her hands and holding a knife. Sean says that when he used that half, he saw himself die from a stab wound.

The team puts together that Sean used the vision of Ed Morgan to blackmail him and theorize that Sean's future death will come from Ed, paranoid and depressed. Both men are tracked down to Sean's flat. Gwen manages to disarm Ed, averting the future Sean saw, and to talk down Owen when he, still traumatised by witnessing the rape, vengefully tries to shoot Ed. But Ed, in a fit of depression, deliberately walks onto the blade Gwen's holding, fulfilling her vision. The device is placed in the secure archives in the Hub.

Tropes

 * Actor Allusion: Ed's death is deliberately staged to recall the death of Blake, the title character that Gareth Thomas played in Blakes Seven. Also, immediately after leaving Blake's 7, Thomas starred in Morgan's Boy, a non-SF series in which he played a character named Morgan who killed himself at the end.
 * Death Seeker: Ed Morgan
 * Dreaming of Times Gone By: What the first part of the transducer does.
 * Dreaming of Things to Come: What the second part of the transducer does.
 * Dual-Wielding: Gwen, during her Training Montage.
 * The Empath: The quantum transducer can turn people into this. They feel the emotions of the ghost in question.
 * Idiot Ball: Gwen may be new at this, but one would think just activating an alien device because it's blinking would be taking a severe amount of risk.
 * Inherently Funny Words: Splott, a district of Cardiff Torchwood ends up visiting. It's noted that the locals prefer "Sploh".
 * Mundane Solution: Sorry, Tosh, but the answer to tracking down our targets is not a complicated database. The phone book works just fine.
 * Rape as Drama: Poor Lizzie.
 * These Are Things Man Was Not Meant to Know: Naturally, Jack has some reservation over people seeing The Future.
 * You Can't Fight Fate: Or can you? Sean saw himself die, but it was averted. Gwen saw herself covered in someone else's blood, holding a knife, and that certainly happened, although not the way she expected.