The best on the box tonight.
Mad Dog: Gaddafi's Secret World
This 'Storyville' documentary examines the nightmarish 42-year rule of Libyan dictator Muammar Gaddafi with the help of eye-witnesses, including an FBI man who encountered Gaddafi's globetrotting death squad.
Channel 4, 9.00pm
Davina McCall and Alex Brooker introduce the final of this week-long celebrity winter games contest staged high in the Austrian Alps, as the remaining contestants face more grief on the ski slopes and bobsleigh tracks before a winner is chosen.
In February of last year, Jeff Bush was at home in Florida when a giant sinkhole opened up beneath his bedroom and swallowed him whole. Professor Iain Stewart (right) travels to the US state to find out why the area's geology makes it the sinkhole capital of the world.
Stephen Tompkinson returns in a new series of the drama based on Peter Robinson's novels. When a man and woman claiming to be social workers visit a mother and tell her they need to take her son away, Banks is drawn into a full-scale search for the boy.