Genevieve (film) - Wikipedia

1hr 26mins
Dir: Henry Cornelius
Starring: Kenneth More and Dinah Sheridan

Two couples race each other on their way back from the London-Brighton car rally

This classic comedy features a railway scene towards the end. The scene where Kenneth More and John Gregson almost come to blows was filmed at the junction between Tavistock Road and High Street close to West Drayton station. In the unedited versions of the film, a train hauled by a large 2-6-2 tank locomotive (almost certainly a 6100 Class) can be glimpsed passing behind the pair on an embankment at the top of the screen, though the train is partially obscured by a wall. The tram lines seen near the end of the film where not in Westminster, as implied by the cast, but were in the Stockwell and Old Kent Road areas of South West London where the defunct lines were still present in the road at the time of filming, only a year after London’s tram services had ceased.

Genevieve takes centre stage in this shot but just next to ‘The People’s Snack Bar’ sign top right is a large GWR Prairie Tank working a service into London. The train is passing the junction with the Colnbrook branch on the approach to West Drayton station from the west.
And just for the record this is the Old Kent Road with the old tram lines still embedded in the road surface