Fans of The Chase are having to do a double take as Mark Labbett shows off his incredible transformation.Towering Mark, 54, weighed 27 stone at his heaviest before he managed to shift the pounds last year.The brain box, nicknamed The Beast on the hit ITV quiz show, has wowed viewers as the weight continues to drop off.The New Year is treating the Chaser well if his latest Instagram updates are anything to go by.