Chick 1 says:

You probably already know that when Heath Ledger died tragically two years ago, he was in the middle of filming the Imaginarium of Dr. Parnassus.  The creative team behind the film, led by director Terry Gilliam, came up with what I think was an inspired solution to losing their star.  Apparently, the story involved Ledger’s character going through a mirror (a la Alice) three times.  When Ledger died, he had completed filming almost all the scenes on one side of the mirror.  Read more