Big Brother's Bit on the Psych presenter Rylan Clark, impressionist Debra Stephenson and former Doctor Who star Colin Baker take part in the quiz show in which contestants answer questions to win turns on an arcade-style machine. Dropping tokens down a choice of four chutes, they hope to knock piles of them off a moving shelf - and the more they gather, the better their chances of collecting the £20,000 prize for their selected charity.