Revealing mistake: When Dominic West is captured and chained in the Pict village, you can see a hearing device in his ear. (00:38:55 - 00:41:35)
Revealing mistake: When Mark gets a nasty note from a Harvard classmate and storms out of a computer class, a directory sign saying "USC College of Letters, Arts & Sciences" (ie. University of Southern California, not Harvard) can easily be seen on the hallway wall through the door as he opens it and walks out.