Gary Sparrow is an ordinary bloke in 1990s Britain, married to the ambitious Yvonne and working as a TV repairman. Then his whole world changes when he stumbles upon a portal to WWII-era London and begins a dual life as an accidental time traveler.
Whilst advancing through the time warp, a severe storm in 1944 causes Gary to split into two opposing clones: a regular Gary and an evil clone. Phoebe likes the former, while Yvonne prefers latter.
Gary and Yvonne have a bust-up which ends with Gary having to move into Ron's place. During Gary's estrangement, he becomes suspicious of Yvonne's interior designer. Meanwhile, in 1944, Phoebe suspects that Gary is having an affair with Yvonne, and Reg contracts impetigo.
Gary has to think fast when both of his wives decide they want to emigrate to California. In 1944, Reg retires from his job, but no one turns up at his leaving do.
Gary and Phoebe are cast in Noel's film Brief Encounter, but Gary declines. Meanwhile, both Phoebe and Yvonne catch the attentions of other men, which Gary resents and intercepts.
A foggy night in London leads Gary into the unknown time territory of 1880. Here, Gary comes face to face with the notorious Jack the Ripper, who manages to access the portal.
When a workman arrives to carryout repairs in the time portal alleyway, Gary begins to contemplate where his future lies.
Gary thinks that Yvonne is having an affair, so he asks Ron to spy on her for him. Plus, Gary and Phoebe join a concert troupe in Belgium, but their efforts are quickly thwarted.
Gary and Phoebe come up against the bully tactics of a protection racket, so Gary utilises his modern gadgets to halt their reign of terror. Plus, Yvonne receives a rude surprise.
Gary must ensure that a compromising photo taken of him in the 1940s avoids discovery in the present. Yvonne goes to see Noël's Gary and Phoebe stage play.
It's 1945 and VE Day celebrations are in full swing. Future Prime Minister Clement Attlee is in town to join in with the festivities. Gary finds himself rushing to Attlee's aid when disaster strikes.
