[This article contains SPOILERS for Hannibal season 2.]
The last time that we saw Mason Verger (as played by Michael Pitt) on Hannibal, the sadistic meat-packing industry figure had received a taste of his own medicine, after being drugged by Dr. Lecter (Mads Mikkelsen), who then led Mason to chop up his own face and feed it to Will Graham's (Hugh Dancy) dogs... while also having Mason snack on his own nose (a nasty mix of bleak comedy and gruesome violence, even by the show's Grand Guignol standards). Which is to say that, in the aftermath, Mason wasn't quite as recognizable as his old self.
For that reason, the news that Pitt is being replaced by Joe Anderson as Mason (on Hannibal's upcoming third season) is less of a big deal, seeing as neither actor would have been recognizable in the role given the character's current physical state (more on that later). Anderson is a character actor whose big screen work includes roles in Across the Universe, The Crazies, and The Grey; he more recently appeared on a pair of fairly short-lived genre TV shows, The River and The Divide.
Katharine Isabelle will be returning for Hannibal season three as Margot Verger, who's up for some payback against her brother. Mason, meanwhile, appears to have found a henchman to help take revenge against Dr. Lecter, as TVLine says the character's newly-hired personal doctor - an intelligent man named Cordell, who's also "definitely creepy" - is not only good at caring for his boss, but seems to share dark tendencies that would make him useful in any criminal activities Mason plans out.
TVLine also reports that it was Pitt's decision not to reprise as Mason on Hannibal's third season; perhaps he wasn't interested in acting under all the makeup and prosthetics that the character will require hereon out. Whatever the reason, though, Anderson is taking over, and the actor has unveiled (via Instagram) a picture of himself as the mutilated Mr. Verger. As you can see below, he'll be as unrecognizable in the role as Gary Oldman was, back when he portrayed an older Mason in Ridley Scott's Hannibal (the 2001 movie).
Hannibal season three will pick up a year after the bloody finale to season two, as we find out for certain who lived (and who died) during the showdown that took place at Dr. Lecter's home in "Mizumono". Mikkelsen's Lecter, meanwhile, has been spending that time in Europe with Dr. Bedevil Du Maurier (Gillian Anderson), and the latter will continue to play a significant role in the overarching story in the episodes ahead, now that Anderson's been upgraded to recurring cast member status.
This next season of Bryan Fuller's acclaimed TV series will also explore the backstory for Hannibal's Dr. Lecter, as we meet a key figure from his past; one all too familiar with the brilliant doctor's serial killer tendencies. Suffice it to say, many a Hannibal fan is anticipating this revisionist take on the title character's upbringing and background - a slight departure from the Lecter backstory in what is the largely critically-despised Hannibal Rising (both Thomas Harris' source novel and the subsequent film adaptation).
Hannibal season three will air on NBC in 2015.