Tonight in HD: August 18

Chuck (TV2, 8.30)

Friends (TV2, 6.30, R) ✫✫✫✫

Chandler’s irrational fear causes problems when Phoebe brings home a cute dog; Rachel’s assistant gives her a Thanksgiving surprise.

Shortland Street (TV2, 7.00) ✫✫✫

Callum takes Hunter under his wing; Gabrielle’s lie gets out of control; Sarah hides a dangerous secret.

Chuck (TV2, 8.30) ✫✫✫✫

Chuck fears that a major loss may end his spy career – and his relationship with Sarah. Summer Glau (Terminator: The Sarah Connor Chronicles) guest stars. Reviews: TV Overmind, IGN, AV Club.

Fringe (TV2, 10.30) ✫✫✫✫

The Fringe team investigates an intense case when a scientist falls dead after ingesting a lethal cloud of blue powder and his bones disintegrate in his body. Reviews: IGN, ScreenCrave.

Life on Mars (TV3, 12.00, 5.1, R) ✫✫✫

When student radicals from the Weather Underground target the police with bomb threats, it becomes all too personal for Lt Hunt, who loses several close friends in the incendiary aftermath.

Criminal Minds (TV One, 12.15, R) ✫