Acting is a craft of deception. As an audience, we're expected to sit and watch famous actors we already recognise playing different characters as if they've never played someone else before. Weirdly, it's mostly just second nature, because of that wonderful thing they call imagination.
Occasionally though, there are actors who struggle to cast off former characters and end up being typecast or facing audiences never accepting them as playing anyone other than slight variants of their most infamous role. In that respect, you can understand why some of them go through incredible transformations for roles.
Obviously there are method actors who drop and gain weight at will in preparation for roles, but there are also some who, through visual trickery, effects and prosthetics manage to completely change themselves to such a degree that you don't recognise them at all...
10. Rhys Ifans - The King's Man
Coming in February (not always a concerning release window, these days), the Kingsmen prequel that will establish the origin of Her Majesty's Other Secret Service looks a bit of a winner. The cast - led by Ralph Fiennes, young Harris Dickinson and Gemma Arterton - looks great and the story, centred around the start of the First World War is an intriguing one.
Most interesting of all the cast is Rhys Ifans part as notorious Russian mystic Grigori Rasputin, who grew a rather romanticised reputation for temporary immortality after his death. Sounds contradictory, but Rasputin and unkillable tend to go hand in hand.
Anyway, Ifans looks the part as Rasputin, complete with straggly hair and long beard, with make-up used to make his eyes look dark and deep-seat and if you didn't know it was him, you'd be forgiven for missing the fact entirely.