Taskmaster: Am I an Idiom?

Little Alex Horne has a lot of fun administering a task involving ducks and mystery. But while that may be his favourite sort of task, it's not appreciated by everyone - especially Sanjeev Bhaskar. Ania Magliano makes a noise like a small cat, Maisie Adam becomes smug, Reece Shearsmith balances on one leg for an impressive length of time, while Phil Ellis struggles to open a door as the challenges continue to be dished out by Greg Davies