Tonight in HD: August 4

Fringe's Christopher Lloyd (TV2, 10.30)

Friends (TV2, 6.30, R)

Chandler finds the perfect engagement ring and loses it; Rachel gets her wish for Paul to reveal his emotions, but seems to have opened the flood gates. Bruce Willis guest stars.

Shortland Street (TV2, 7.00)

Bella is horrified at Nicole’s streaking; TK struggles to accept Sarah’s decision; Lana goes a step too far.

Chuck (TV2, 8.30)

Chuck’s dream of finding his mum may be his worst nightmare. Plus, it’s Halloween at the Buy More. Morgan Fairchild guest stars. Reviews: IGN, AV Club, What’s Alan Watching?

Fringe (TV2, 10.30)

An observer makes contact with the Fringe team to help rectify a mistake; Walter befriends one of his musical heroes. Christopher Lloyd guest stars. Reviews: Time, Los Angeles Times, TV Squad.

Criminal Minds (TV One, 12.00, R)

A serial killer targeting couples stages their bodies in a way to make their deaths look like car accidents.

Life on Mars (TV3, 12.00, 5.1, R)

A New York councilman shares a stunning secret with Sam that leaves him with more questions than answers.