River Patrol (film)

River Patrol is a 1948 British crime film directed by Ben R. Hart and starring John Blythe, Lorna Dean, and Wally Patch. A group of undercover British customs officer investigate a gang of nylon smugglers. It was made by Hammer Film Productions as a supporting feature. It was made at Marylebone Studios in London. It is notable for being one of the earliest films made by Hammer following its relaunch after the Second World War.

Source: Wikipedia