The Great Christmas Bake Off 2021: Lydia West A huge part of the charm of It's a Sin was that a significant number of the cast members were up-and-coming actors at the start of their careers. Lydia West, whose character Jill is full of heart, had previously only appeared in two TV productions prior to her breakout performance. A burgeoning baking career could also be on the horizon for Lydia, if she becomes the Christmas star baker, that is. Image Source: Getty / Tim P. Whitby