Crooks and Coronets plot
"The caper could get $5,000,000. All these American hoods had to do was knock off the nice old lady in World War I flying garb, the eccentric gentleman with the crossbow and the man-eating lion."
While in prison, Herbie learned of the country houses in England, which are full of valuable art and jewels. An art collector wants to provide him with the resources in exchange for hard-to-obtain additions to his collection. In their preliminary work, however, they get the opportunity to get to know the sweet old lady better, which is not good for the execution of the plan.