The Beverly Hillbillies - Season 4 Episode 4 The Private Eye
Overview: Jethro is a 'double nought' spy waiting for a call from 'M' so he can go on an adventure. Mr Drysdale gives him an office in the bank & Elly May is his secretary. After a visit from two other 'agents' Jethro thinks he's on his way. However the two 'agents' know Jethro's office is above the Bank's Vault & want to break in to it until the double nought spy foils their plan.!