Tome-Wan would at first appear to be one of these interstitial episodes between momentous events, but a number of important events happen in this episode , so its not filler.
There are a number of confrontations, in the aftermath of Will snitching to Mason about how the whole situation between Mason, Margot, and Will was orchestrated by Hannibal.
Will tells Hannibal what he said to Mason, and when Hannibal asks why, he tells him he wanted to see what would happen, throwing back at Hannibal his excuse for why Hannibal warned Garrett Jacob-Hobbes, long ago in that first episode. There are a number of callbacks by Will to that first season.
Hannibal asks Will to close his eyes and imagine what he’d like Mason to do to Hannibal. Will imagines Hannibal hanging from the rafters in Mason’s pigpen, wearing a straitjacket. In his mind he is the one who slits Hannibal’s throat. Will is suffering from a severe case of “lovehate”. Hannibal has been the architect of so much misery that he can’t wait to see him dead (or captured). At the same time, there’s a part of him that finds all of this exciting, and revels in Hannibal’s antics. Will gets to use his hidden savage self in service to the state, and loves letting that part of himself of its leash. You can see it in the last episode where he confronted Mason.
Mason confronts Hannibal during his next therapy session. He’s being especially hard on Hannibal’s nerves, as he critiques his drawings, declaring them to be crap, throwing his feet onto Hannibal’s desk, and stabbing at them with a penknife, like a bratty ten year old, which is exactly where Mason is, mentally. He hasn’t evolved beyond the spoiled child stage, and doesn’t seem to realize that he is dealing with a wholly different type of animal than anything he’s ever encountered. Mason is a small fish that, because of his narcissism, thinks he’s pretty big, in a big pond. He doesn’t even conceive that he’s dealing with Hannibal the Great White.
Mason tells Hannibal that he should have stayed out of Verger family business, and threatens to slit his throat. Hannibal, who never gives anything of himself away, acts completely unperturbed, so you know that Mason is a walking dead man, and that Hannibal have to do this himself, since Will isn’t cooperating with his masterplan of having Will kill Mason. Watch Hannibal’s face during this scene. You can see he is barely holding himself back from snapping the shit outta that little fucker. (Not in the office, Hannibal! Not in the office! – In the voice of Last Week’s John Oliver.)
In Margot’s therapy session with Hannibal, she is broken and restrained. After her forced hysterectomy, (which his quite possibly one of the most heinous things ever done on this show, and that’s saying something, when you consider this is a a show about serial killers.), she has learned her lesson about trying to oppose her brother, and all her hope is lost.In fact all seems lost for everyone, as there are a number of setbacks for all the characters, in this episode.
Jack Crawford, who is frustrated at how long its taking Will to ensnare Hannibal, has a surprise for Will. He has found and detained Bedelia Du’Maurier, Hannibal’s former psychiatrist. She tried to run away because she knew Hannibal was dangerous for her, but the FBI has done her the favor of putting her back on his radar, as he was too busy with his machinations with Will, to search for her himself.
Will questions Bedelia about Hannibal’s weaknesses. She tells him of her fear of him, how he manipulates others into doing his dirty work for him, something which Will is experiencing first hand, and confesses about the patient Hannibal set her up to kill.She says Hannibal will persuade Will to kill someone he loves, but the only person Will has left to love is Alana. Hannibal has carefully removed everyone else from Will’s life, including the idea of his unborn child.
Hannibal may be aware of how much Will hates him, during their next therapy session, but he completely disregards the depths to which Will will sink in pursuit of him. Will accuses Hannibal of fostering co-dependency. Hannibal doesn’t want anyone in Will’s life but himself. Which, when you think about it, is one of Hannibal’s creepier aspects.
While Hannibal is drawing one evening, Mason’s henchman, Carlo, bursts in and kidnaps Hannibal, but not without a fight in which Mateo, a friend of Carlo, loses his life, after Hannibal stabs him in the femoral artery with a scalpel.. Carlo stuns Hannibal, takes him to Muskrat Farm, and trusses him over Mason’s pigpen. This is directly from the book and movie, Hannibal, where Mason Verger has Hannibal in this same position.
Just as in his imagining, Will is prodded by Mason to slit Hannibal’s throat. We’re not sure exactly whats going on in Will’s mind. He certainly hates Hannibal, but when given an opportunity to kill him he balks, and later when given the opportunity to capture Hannibal, he warns him instead. Does Will even know what he wants, or why? Instead of cutting his throat, Will frees Hannibal but gets knocked out by Carlo for his troubles. Hannibal just leaves Will there unconscious and spirits Mason away for some, more private, torture.
When Will wakes up he finds blood streaked everywhere, no sign of mason and Carlo’s body, which was eaten by the pigs. He goes back to his home to find Hannibal there with Mason. Hannibal has drugged Mason and induced him to cut off pieces of his flesh, using his father’s knife, and feed it to Will’s dogs. I’m not sure how lost Will is in this scene. He seems amused at what Hannibal is doing. Is he happy because he finally has evidence of Hannibal doing something actionable in front of him, or is he simply amused at Hannibal’s antics? In a nastily gruesome scene, Hannibal also orders Mason to cut off his lips and nose, and eat them. What makes this scene especially grotesque is Mason’s mental state. As he happily mutilates his face, he still crack plenty of jokes, about it.
Finally disturbed , Will urges Hannibal to finish Mason, but canny predator that he is, Hannibal doesn’t kill Mason. Instead he carefully paralyzes Mason with a precise break of his neck.
Weeks later, Jack Crawford questions Mason about what happened to him, but Mason says he fell into his own pigpen, and sings nothing but praises for Hannibal Lecter’s care. But we know better. This shit ain’t over as far as Mason is concerned. Or maybe it is. As Jack leaves, Mason is confronted by Margot, who tells him that she will take very good care of him. She’s the one in power now. I really love this scene, for the look of deep gratification on Margot’s face, as she says this.
Later, Will and Hannibal are debating whether to confess their sins to Jack, or not. Hannibal weighs the idea that Jack should be told, and then killed, after which he and Will will run off together.