The Road to Hong Kong (1962)

In their final road movie together, Hope and Crosby return as hucksters Chester and Harry. When Chester loses his memory, they are told his only hope is to go to a lamasery where they have an herbal remedy to restore it (and where another herb will enhance it ). Through a case of mistaken identity while en route, they get their hands on some sensitive material, the only copy of which winds up in Chester's head. Unfortunately for them, an agent of the high lama retrieves the herb they stole, thus making it impossible for them to recall the memorized information on demand - and the nefarious people who desperately want it are willing to do whatever it takes to get it.