Season 1 and 2 spoilers ahead! Only spoilers from Season 3 should be blanked out.
Introduced in Season One
A feathered stag that appears in Will's dreams and hallucinations that represents Will and Hannibal's relationship.
- Arc Symbol: Word of God: "The stag always represented the connection between Will Graham and Hannibal Lecter. He started seeing the stag after he was first exposed to Hannibal's murder of Cassie Boyle impaled on the stag head in the field." 
- The Marvelous Deer Marvelous but more on the mysterious and haunting side.
A monstrous being who appears in Will Graham's dreams and hallucinations. The Wendigo appears as a man with stag horns and charred skin.
- Arc Symbol: Wendigo represents Hannibal's evil influence and cannibalism.
- The Bus Came Back: Reappears in "Contorno" for the first time since the Season 2 finale.
- Dark Is Evil: The Wendigo has charred, blackened skin, as if to evoke Georgia's charred corpse in Season 1.
- Glamour Failure: Played with. On several occasions, Will has suddenly seen the Wendigo standing in Hannibal's place. When Will sees the Wendigo, it represents his awareness of Hannibal's monstrous nature.
- Horned Humanoid
- Humanoid Abomination
- The Voiceless
- Wendigo: In Algonquian folklore, people who indulge in cannibalism transform into wendigos, making the creature an appropriate symbol for Hannibal.
One of Hannibal's patients.
- Abhorrent Admirer: To Hannibal.
- Alliterative Name: Franklyn Froidevaux.
- Ambiguously Gay: While he admits to having "tried things" (finger quotes and all) while he was in a fraternity, he denies having any sexual feelings towards his friend, Tobias. Any feelings towards Hannibal, on the other hand, are rather ambiguous.
- Birds of a Feather: He firmly and mistakenly believes that he and Hannibal are this.
- Captain Ersatz: According to Word of God, he is one of Benjamin Raspail.
- Cloudcuckoolander: Talking about cheese for too long, his peculiar tangent about being friends with Michael Jackson, and utterly failing to recognize that neither of the people he wants as "friends" actually like him. At all.
- Desperately Craves Affection: He mostly just really wants a friend.
- Experimented in College: Franklyn admits to having "tried things" in a fraternity.
- Forbidden Friendship: He desperately wants to be friends with Hannibal, who reminds him that they cannot be friends because of their doctor-patient relationship. Franklyn was referred around to nine different doctors before Hannibal, suggesting that he behaved in a similarly inappropriate manner toward his previous psychiatrists.
- Horrible Judge of Character: He thinks Hannibal is a great guy with lots in common with him and doesn't think anything's wrong with Tobias until he outright talks about wanting to kill people. In detail. But even more egregious is his completely misjudged attempt to psychoanalyze and reason with Tobias, who he reads as conflicted and distraught when Tobias is really looking forward to killing him.
- I Just Want to Be Special: Franklyn's self-worth is entirely tied not just to being liked, but to being liked by famous or talented people.
- Inelegant Blubbering: He has a tendency to descend into semi-incoherent tears.
- Ironic Death: Hannibal compares Franklyn's neurotic tendencies to feeling as if there is a lion in the room, and assures Franklyn that if a lion were actually there, Franklyn would know. In the end, Franklyn fails to notice both lions in the room.
- Neck Snap: Hannibal snaps his neck in "Fromage".
- No Social Skills: He's lousy at reading people, says inappropriate or odd things, and doesn't seem to understand that he's stalking his therapist.
- Small Name, Big Ego: His desire to aid, befriend and counsel those more powerful or accomplished than himself means that he has a vastly overestimated sense of his psychoanalytical skills — not only does he start playing therapist during one of his later appointments (which Hannibal chides him for), but he actually attempts to patronizingly negotiate with Tobias, a determined and unrepentant psychopath bent on murdering him.
- Stalker with a Crush: Starts behaving this way towards Hannibal in "Sorbet". It's also very likely that Hannibal is not the first therapist he's stalked — he's been referred nine times, which he calls being "dumped".
- The Power of Friendship: He believes Michael Jackson wouldn't have died if they had been friends.
- Transparent Closet: As seen above, when Hannibal questions his sexuality, Franklyn reacts defensively, admitting experimentation while in a fraternity, but denying being gay. The viewer can take it at face value or interpret it as denial. Though both are valid interpretations, the majority of the viewers have agreed on this trope, with some of them choosing this interpretation because Benjamin Raspail is a gay man in the source material.
- With Friends Like These...: When Franklyn introduces his "friend" Tobias to Hannibal, Tobias states that Franklyn seemed more interested in staring at Hannibal than watching the show.
Dr. Donald Sutcliffe
A Baltimore-based neurologist, was a colleague of Hannibal Lecter's when both were young doctors at Johns Hopkins Hospital.
- Asshole Victim: Hannibal kills him and frames Georgia for it.
- Blatant Lies: He tells Will that his tests came up normal, knowing full well that Will has encephalitis.
- For Science!: When Hannibal comes to him with an offer to commit blatant malpractice, this is his reasoning. It's not often you get to study a person with this condition as they deteriorate in real time.
- Jerkass: He constantly snarks at Hannibal about the superiority of neurology over psychiatry, refers to Will as Hannibal's "pig", and lies to Will about his diagnosis.
- Karmic Death: He happily agrees to Hannibal's scheme to conceal Will's condition from him, not realizing Hannibal is planning to kill him to drive Will further over the edge.
- Morally Ambiguous Doctorate: He lies to Will about his encephalitis, intrigued by the opportunity to study him without his knowledge.
- Named After Somebody Famous: Named after Peter Sutcliffe, an infamous serial killer nicknamed The Yorkshire Ripper.
Introduced in Season Two
Will Graham's attorney in Season 2.
- Amoral Attorney: Played with. While he's working diligently to save Will from a guilty verdict, his means are manipulative.
- The Cynic: He's fully aware that the criminal justice system is flawed and that emotional manipulation, not necessarily evidence or logic, is the key to winning court cases. He even likens his work to advertising, in which attorneys "sell" listeners a case.
- Deadpan Snarker: He's wonderfully snarky toward everyone.
- Good Is Not Nice: He may be representing Will and struggling to keep him from being found guilty, but he's a cynical man using manipulative means in the courtroom.
- Jerkass: He's cynical and rude, particularly in his interactions with Alana.
- Jerkass Has a Point: During a practice testimony session, he bluntly warns Alana that her icy composure won't play well in the courtroom, and that her testimony will require a different emotional approach.
A mentally disabled man whom Will Graham questions about a murder in "Su-zakana".
- Adopt The Animal: Peter's first and foremost concern is always about the animals in his care, or even those that he's never seen or interacted with before. The sheer amount of animals he's able to successfully care for, all by himself, is quite impressive.
- Berserk Button: One of the first things that Will deduces about Peter is that he's very non-aggressive and avoids confrontation at all costs. But hurt his beloved animals? Yeah, all bets are off after that.
- The Dog Bites Back: After his social worker Clark Ingram manipulates him, frames him, and releases all his pets, Peter overpowers and sews him into a dead horse so that he'll understand how his victims suffered.
- Disabled Means Helpless: Subverted. While Peter is psychologically vulnerable, he's capable of caring for multiple animals and turning the tables on Clark Ingram.
- Frame-Up: His social worker tries to frame him for a series of murders.
- Friend to All Living Things: His barn is full of animals. When he learns the FBI discovered the starling in a murder victim's body, he voices his concern about who's caring for it. Even when he's locked up, he keeps a rat in his sleeve. He also asks Will not to blame the animal in a murder by animal attack, since "man is the only animal that kills to kill."
- Kick the Dog: Clark Ingram releases all his animals and kills a horse in his barn.
- Manchild: But not of the annoying or rude variety. Peter's exceptionally compassionate and good with animals, but has difficulty interacting with people beyond a toddler-like level due to his traumatic brain injury.
- Meaningful Name: Word of God states that he is named after Giovani Pietro Bernardone, aka Saint Francis of Assisi, the Patron Saint of Animals.
- Not So Different: From Will Graham. Both Peter and Will were manipulated and framed by men who were supposed to help them. And both of them love animals.
- Speech Impediment: He was kicked in the head by a horse. Because of his brain damage, his speech is slurred and halting.
- A Taste of Their Own Medicine: He sews Clark Ingram up in a dead horse, to give him a taste of the despair his victims felt.
Introduced in Season Three
A hedonistic poet and socialite who encounters Hannibal during his brief stay in Paris, and later again in Florence.
- The Alcoholic / Functional Addict: Implied to be this, judging by his "double-fisting" of two champagne glasses in Paris.
- Blackmail: Attempts this on Hannibal. Results in Blackmail Backfire.
- Body Horror: The final result of his corpse. Hannibal skinned him, folded it into a gigantic heart and placed him in the middle of the Norman Cathedral. And this is shown in all of its gory detail.
- Deadpan Snarker: In a smug, nasty sort of way.
- Death by Irony: In a roundabout way. Dimmond talked about how Hannibal was twisting himself into an uncomfortable position by posing as Roman Fell, and offered to "untwist" him, which here is a euphemism for extortion. Hannibal proceeds to snap his neck, skin his body and forcefully fold him into the shape of a human heart. In other words, Dimmond was twisted into an extremely uncomfortable position.
- Depraved Bisexual: Attempted to blackmail Hannibal and Bedelia into sex in exchange for keeping Hannibal's cover story as Roman Fell.
- Jerkass: Badmouths his old professor (during a party in his honor) to Hannibal, a complete stranger, when he meets him for the first time, to an uncomfortable degree.
- Neck Snap: How Hannibal offs him.
- Smug Snake: He somehow considers himself smart enough to blackmail Hannibal.
- Too Dumb to Live: He somehow thinks that he'll successfully blackmail a couple who he believes has already killed two people. He tells nobody his suspicions, creates no back-up plan and doesn't seem to entertain the possibility, or rather probability, that he's a loose end that needs tying up.
Inspector Rinaldo Pazzi
A disgraced detective in Florence, Italy. Is determined to catch Hannibal Lecter for a series of murders he committed as a youth.
- Cruel and Unusual Death: Disembowelled and hanged, given a perfect view of his own entrails splattering the ground before he dies.
- Death by Irony: Hannibal arranges for him to die in the same manner as his famous ancestor: hanging while disembowelled.
- Dirty Cop: Claims Mason Verger's bounty rather than catch Hannibal through legal means. This leads directly to his death when he has no backup to rescue him.
- Fatal Flaw: Greed. With official backup he could have had an actual chance to catch Hannibal, or at least make it out alive. But he wanted Verger's bounty so badly...
- Foil: To Will, claiming he possesses the gift of "imagination" that Will has. His personal search for Il Monstro and being a married man also mirrors Jack, whose obsession in catching Hannibal cost him his career and nearly his life. Unfortunately for Pazzi, he doesn't survive the experience like Jack.
- Friend on the Force: Acts as Will's connection in the Italian police.
- Genre Blind: Sure, try to catch Hannibal on your own. It's not like he has superior perception and could see your plan coming from a mile...
- Happily Married: From what little is seen of him with his wife.
- Hardboiled Detective: He seems to really wish he was one.
- My Greatest Failure: His inability to find any evidence against Hannibal for the Il Mostro killings twenty years ago led to a man innocent of the crimes being convicted, and Pazzi's reputation being tarnished.
A former patient of Bedelia Du Maurier, who died before the series began.
- Big Ol' Eyebrows: Due to being played by Zachary Quinto.
- Cruel and Unusual Death: He choked on his own tongue, which "wasn't attached at the time." That's because Bedelia shoved it down his throat.
- The Insomniac: Neal had mild trouble sleeping, which was why he went to see Hannibal. Of course, under Hannibal's "care" it spiraled into full-blown insomnia.
- Posthumous Character: Died prior to the series, and will only appear in flashbacks in the coming season.
- Properly Paranoid: Believed that something was wrong with Hannibal and was trying to purposefully exacerbate his insomnia and depression to control him. He was right, but he does recognise that he suffers paranoid tendencies separately. Hannibal was indeed using photo therapy on Neal, saying that it was supposed to manage his circadian rhythms, but like with Will he was using it to hypnotize Neal.
- Small Role, Big Impact: He only appears in a flashback and is already dead prior to the series, and his death is a major part of Bedelia's story. The flashback reveals that Hannibal hypnotized him into choking on his tongue when he gets upset, and is actually nothing more than another innocent victim. Bedelia was even going to prescribe the same therapy he was getting from Hannibal. When he calls her out on it and starts to choke, she shoved his tongue down his throat instead of saving him. In other words, she lied about his death, which throws her previous characterization for a loop and implies she's actually Not So Different from Hannibal when talking to Will.
- Suspiciously Similar Substitute: To Will Graham, though in this case it was Neal who came first. Like Will, Hannibal took an interest in Neal and proceeded to take advantage of his ailment (in Will's case his encephalitis while Neal had insomnia) and used light-based hypnotism to induce fugue states and increase their potential for violent tendencies.