Gary and his son Michael are blasted into present time by a 1944 air raid bomb. They are caught by Yvonne, who demands an explanation regarding the child's identity.

In the present and wartime 1944, both Gary and Phoebe find themselves being refused entry into higher society circles.

The detonation of an unexploded bomb in Duckett's Passage catapults Gary and Phoebe into the present. Consequently, Phoebe and Yvonne meet for the first time.

Gary tries to persuade Ron to give up his time travelling ambitions, while Yvonne begins consulting for Chelsea FC, pleasing Gary, especially when she acquires match tickets.

Gary tries using his knowledge of the past to bet on certainties at the 1940s race track, but it all goes wrong. Meanwhile, Ron's white fiver printing press is raided by the police.

Gary's assumed identity as a secret agent even fools the 1944 authorities. He is recruited by a genuine M15 agent to go on a secret mission to the Isle of Wight.

Gary's secret mission in wartime France quickly descends into a dicey fight or flight situation, as the German's rapidly close in on him.

As the strain of living a double life takes its toll on Gary, Rolf Harris appears in a dream and berates him for having claimed authorship of 'Two Little Boys.'

The porter of Gary's Mayfair flats informs him that a former resident died in a road accident 55 years ago. Gary aims to travel back to reverse the chain of events.

Gary encounters his 1940s now-adult son Michael, who is shabbily dressed and trying to flog him items. He returns to the past to try and improve Michael's future prospects.