Board Thread:False Info and Speculative Discussion/@comment-27411820-20160211213841/@comment-5285305-20160218073248

We don't know that the Doctors make the Beast shift every night.

The only thing we know for a fact (based on the information given from the show, and what we're shown) is that Mason doesn't have an alibi whenever the Beast shows up on screen, and vice versa.

I personally like the idea of someone who's trying to help, end up becoming the very thing the main characters are fighting.