Keira Knightley, Paul Merton, Gareth Thomas, Paul Hollywood, London Grammar

The host is joined by actress Keira Knightley - starring in Alan Turing biopic The Imitation Game and romantic comedy Say When - quick-witted Have I Got News for You team captain Paul Merton and Welsh rugby hero Gareth Thomas. Plus, Great British Bake Off judge Paul Hollywood and music by electro-pop trio London Grammar.