Switch (1975)

Former bunco detective Frank MacBride joins forces with a con artist he once sent to jail, Pete Ryan, to operate their own private detective agency. Most of their cases involve running cons on the bad guys in order to trick them into surrendering or revealing the whereabouts of the stolen loot, jewels, etc. Maggie was their cute receptionist, and wacky restauranteur Malcolm, whose mastery of disguise often came in handy in helping MacBride and Ryan on their cases, provided the comic relief.