Killer Lakes Pearl, 9.30pm In 1984 at Lake Monoun, in Cameroon, 37 people were found dead with no clues to what happened. A bizarre array of theories sprang up - secret testing of chemical weapons, a massacre by unknown terrorists - but none really made sense. The scientists who looked into the disaster believed it had to be something to do with the lake itself, but they could not be absolutely sure. Stripped World, 8.30pm This new series steps behind the cosmetic counter for a revealing look at what goes into creating your favourite beauty products. Starting with lip products, Stripped goes inside the famous CoverGirl factory to find out why the company is turning up the heat, and explores the origins of this colourful cosmetic.