Gentlemen of Fortune (1971)

Kindergarten teacher Evgeniy Ivanovich Troshkin is reluctantly sent undercover to take the place of an imprisoned thief who stole Alexander the Great's helmet. Evgeniy uses his striking resemblance to the thief to infiltrate his gang and learn the location of the stolen artifact. He finds the gangsters are unexpectedly similar to his students- they also need love and care.