ITV has confirmed that Helen, 40, will be joined by a lineup of stars including Sir Lenny Henry, Ade Adepitan, Ross Noble, Dougie Poynter, Lucy Punch, and Countdown's Rachel Riley.

Mirren, 79, stunned fellow actors Kathy Bates, Parker Posey, Niecy Nash-Betts, Keri Russell and Cristin Milioti when they gathered to discuss their craft.