20. Only Ever Half Committed
There's an enduring mythology attached to Anthony Daniels' performance as C-3PO that the actor endured the unthinkable agony of having to wear a chaffing, sweaty golden suit for the entirety of his scenes, committing beyond the usual levels for the full effect of the performance. That idea added something to the idea of the performance, since Daniels' work was so utterly convincing as a non-human entity, and the revelation that at times he wasn't fully committed is a little difficult to take for fans brought up with those expectations.
19. The Headless Ewok
There's just something devastating and grimly irresistible about the sight of an actor in full-costume but minus a head. It tramples all over your pre-established ideals of the character to see the man behind the make-up, and this nos famous shot of Kenny Baker minus his Ewok head is the epitome of that jarring effect. Plus, there's nothing pleasant about seeing an Ewok robbed of his head and brandished by a manic looking human, creating the effect of a craved headhunter running amok on Endor, wearing the spoils of his hunting.