He had smaller roles as Doobby in Planes, Trains and Automobiles, Sergeant Larry Balzak in Home Alone, Mr. Heckles in Friends, and Joe in Breaking Bad and El Camino.

[9] Hankin was an early member of the Second City, training with improvisational theater teachers Viola Spolin and Paul Sills, and in 1963 moved to San Francisco to co-found the improv troupe, The Committee.

He had cameo appearances in three John Hughes films: Planes, Trains and Automobiles (1987), She's Having a Baby (1988), and Home Alone (1990), the latter of which coincidentally featured Roberts Blossom (playing Old Man Marley), whom he co-starred with in Escape from Alcatraz.

He made a brief appearance in Pretty Woman (1990) as the landlord, and had minor roles in Loose Shoes (1980), as "Handicap" in The Sting II (1983), The Sure Thing (1985), and Running Scared (1986).

Hankin and Curtis Armstrong played the hippie entrepreneurs who purchased "Buy the Book" (the bookstore where the titular character works at) on Ellen.

Hankin was a founding member of the commedia dell'arte improvisation group The Committee in 1963, located at an indoor bocce ball court in San Francisco's North Beach district.