My Three Sons - Season 9 - Eps 17: What Did You Do Today, Grandpa?
The Douglases feel that Steve is becoming sedentary, not knowing that he's just been assigned to help capture some enemy agents, but things get rough when he's taken to a Greenwich Village cocktail party where the spies start shooting when they find him hiding in the bathtub.
About My Three Sons

Title: My Three Sons
First Air Date: 1960-09-29
Last Air Date: 1972-04-13
Status: Ended
Rating: 6.5/10 (from 33 votes)
Language: EN
Seasons: 12
Total Episodes: 380
Network: CBS
Genres: Comedy, Family
Production Companies: MCA Television, Don Fedderson Productions, Gregg-Don Inc.
Synopsis
A widower and aeronautical engineer named Steven Douglas raises three sons with the help of his father-in-law, and later the boys' great-uncle. An adopted son, a stepdaughter, wives, and another generation of sons join the loving family in later seasons.
Cast

Fred MacMurray
Steve Douglas

Don Grady
Robbie Douglas

Barry Livingston
Ernie Thompson

Stanley Livingston
Chip Douglas

William Demarest
Charley O'Casey

Beverly Garland
Barbara

Tina Cole
Katie

Dawn Lyn
Dodie Harper Douglas