Don't Raise the Bridge, Lower the River is a British made comedy film produced by Walter Shenson starring Jerry Lewis and was released on July 12, 1968 by Columbia Pictures. It was based on Max Wilk's novel of the same name with the original Connecticut locale moved to Swinging London and Portugal.
George Lester (Jerry Lewis) is an American living in England. His passion is get-rich-quick schemes, and they have caused financial and personal grief for him and his wife, Pamela, (Jacqueline Pearce) who is considering divorce if he continues with them.
Willy Homer (Terry-Thomas) is a conman who plans to help George raise some quick cash by selling plans for a drill to a group of Arabians. The plans, which were stolen, are smuggled to Lisbon with help from his accomplice, Fred Davies (Bernard Cribbins). As they are about to trade the plans they realise that they are being double-crossed. A series of chases follow, and eventually the plans are revealed to be worthless to everyone.
Distraught, George finds comfort in his wife and promises to never embark on any more 'get-rich-quick' schemes. That is, until Willy shows up at his door with another one!
It was filmed between May 15 and June