Get Smart (1965)

S3E1 The Spy Who Met Himself

The League of Impersonators from KAOS has infiltrated CONTROL, posing as agents to snatch top-secret warhead plans and create chaos within the organization. When the genuine Max is abducted and swapped with a doppelgänger, he manages to break free. Now, a committee must figure out who the true Max is amidst the confusion of look-alikes!