Heroes: The nefarious Samuel (Robert Knepper) must be stopped before his evil scheme results in thousands of deaths on the sci-fi drama's season finale (9 p.m. NBC).
Intervention: A fitness instructor gets help with her bulimia and an exercise addiction in this new episode (9 p.m. A&E)
Operation Repo: The docu-series about the men and women who take back the goods you can't afford to pay for returns for another season (9 and 9:30 p.m. Tru).
Celebrity Fit Club: More plus-sized C-listers try to shed those extra pounds as the reality competition returns (9 p.m. VH1).
CSI: Miami: The team probes a murder that took place in outer space on a new episode of the forensics drama (10 p.m. CBS).
Be Good Johnny Weir: The Olympic hopeful works with a new choreographer in this new episode of the figure-skating-themed documentary series (10:30 p.m. Sundance).
The Red Carpet Issue: This new documentary explores how the garden variety movie premiere was transformed into a de facto fashion runway (9 p.m. Sundance).
Forgetting Sarah Marshall: Kristen Bell is the lady in question in this charming 2008 comedy costarring Jason Segel and Mila Kunis (9 p.m. HBO).
Pro basketball: The Hornets meet the Magic (5 p.m. TNT) and the Lakers host the Spurs (7:30 p.m. TNT).
