Ted Bessell plays Mary’s new, affectionate boyfriend...

Ted Bessell plays Mary’s new, affectionate boyfriend on The Mary Tyler Moore Show (Sunday at 10 p.m. on Nickelodeon). He also appears on Tuesday’s episode at 10 p.m.

Suzanne Pleshette guest stars on Columbo (Monday at 12:30 p.m. on A&E;) in an episode in which an unstable murder witness complicates his case against America’s leading war hero.

Biography (Tuesday at 5 and 9 p.m. on A&E;) looks at the legendary Sid Caesar. Included are clips from his 1950s series “Your Show of Shows” and interviews with Carl Reiner and Mel Brooks.

Before the force was with him, “Star Wars’s” Mark Hamill appeared on The Partridge Family (Tuesday at 8 p.m. on Nickelodeon) in an episode in which Laurie gets braces.

Set your VCR’s for the classic “Job Switching” episode of I Love Lucy (Tuesday at 9 p.m. on Nickelodeon). Lucy and Ethel get jobs at a candy factory and are forced to work the conveyor belt.

Pat O’Brien, Walter Brennan and Edgar Buchanan star in the charming The Over-the-Hill-Gang (Tuesday at 10:35 p.m. on TBS), 1969 TV movie about a group of retired Texas Rangers who attempt to bring law and order to a Western town run by a corrupt mayor.

David Janssen plays a veteran cop who becomes too emotionally involved in his job on a two-part Police Story (Thursday and Friday at 2 p.m. on A&E;).

Howard Hesseman appears on two episodes of The Bob Newhart Show (Thursday and Friday at 9:30 p.m. on Nickelodeon).

Mary’s arrogant Aunt Flo (Eileen Heckhart) returns on The Mary Tyler Moore Show (Friday at 10:30 p.m. on Nickelodeon). Heckhart currently makes guest appearances on “Love & War” as Jake Stein’s (Jay Thomas) mother.

Very Very Nick at Nite (Saturday at 10 p.m. on Nickelodeon) presents “Very Very Get Rich Quick,” which features Nick at Nite characters scheming to get money in a big hurry.