Ace Lightning's Simon Hollander is a mild mannered accountant — until you insult his son.
Agents of S.H.I.E.L.D.: Coulson shows off his Team Dad status by doing this, particularly for Skye. He pistol-whipped the guy who shot her, and, in general, threatening her in his presence is almost always an awful idea.
Jack Bristow of Alias is a Papa Wolf extraordinaire for his Action Girl daughter Sydney, despite being absent for much of her life due to his job with the CIA. Some of the more memorable instances include the very first line he says in the series being him asking about Sydney's safety (deliberate on the part of the writing staff); breaking another agent's fingers in a vise after finding out he's a traitor, then shooting him in the head after he confesses to exposing Sydney's cover; and entering a fatally radioactive room to ensure her escape.
This is all nothing compared to his retaliation against his own wife, IrinaDerevko. In "Dead Drop", he believes Irina isn't genuine in her desire to help the CIA, so he rigs the safe house Sydney has gone to on Irina's intel to blow, which makes Sydney believe her mother lied to her and meant her harm. As we see in "Search and Rescue", he even executed Irina — or, a double of Irina because he believed she ordered a hit on Sydney.
Mama Bear and Papa Seahorse became proud parents of this trope on Alien Nation, when pregnant Newcomer George Francisco broke with his usual self-controlled civility to utterly cream a thug in defense of the fetal Newcomer in his belly-pouch.
In Andromeda threatening a Nietzschean's wives and children is one of the easiest ways to get them mad at you. Of course this is part of their Social Darwinist values, they are trying to preserve their genes.
Alvaro Cueva, Mexican critic of Alta Definición fame, HATES seeing children being treated as idiots by some shows, and exploited (made fun of or worse, making kids dance in ways pedobear would approve) by others.
Lampshaded: Lorne comments on Angel's strong "Mama Bear Vibe" when he becomes aggressively over-protective of his newborn son. The trope was shown in its full glory when Angel almost smothered Wesley to death after Wesley unwittingly made Angel lose his son.
Then there was this conversation with Lilah:
Lilah: Look, Angel, I know you've been out of the loop for a while, but I'm still evil. I don't do errands. Unless they're evil errands. Angel: I think you'll do this one. Lilah: Why? What's in it for me? Angel: Just this once, I'll ignore the fact that you're within fifty yards of my son. Just this once.
And of course, there was his little speech to Linwood in "Dad" where he promised to inflict upon him any pain Connor experiences, even when Wolfram & Hart couldn't have possibly had anything to do with it.
More seriously, do not harm women Angel cares about — notably Cordelia and Fred.
Michael has a Papa Wolf moment in Arrested Development when trying to get back with a girl he was dating. He stops his sister and mother from physically attacking her in a restaurant for writing an unflattering article about the family. Then he hears that she told his son to stop getting in the way of Michael's happiness. He steps out of the way and tells the girl she's on her own. She promptly gets her ass kicked.
On Spike TV's Bar Rescue, host John sends undercover employees into the failing bars to pretend to be customers; he watches on hidden cameras as they experience the food, beverages, and customer service. On the episode set at J. Murphy's bar, his daughter is one of the undercover workers - and she nearly gets food poisoning from food prepared by a chef who didn't wash her hands after handling raw chicken. John breaks his own protocol and calls off the undercover stint, tears into the bar to stop her from eating the food, and then goes into the kitchen, where he gives the chef possibly the most vicious dressing-down in the history of the show.
In Battlestar Galactica, Commander Adama has shown time and again that he's a very caring Team Dad even with those not related to him by blood, such as Boxy and Starbuck.
While Reimagined, Adama has repeatedly referred to his crew as a family, he's also come dangerously close to sparking off a civil war between the Battlestars Galactica and Pegasus in order to get "[his] men" back.
The scene where he threatens Admiral Cain is both a Moment Of Awesome and example of Awesome Music. "Prelude to War" is a masterpiece and it fits the scene so well. It makes Adama's Papa Wolf-ness that much more badass.
Earlier than that, in the first season episode "You Can't Go Home Again", when Adama puts the fleet and resources in serious jeopardy before giving up on a hopeless rescue operation to recover Starbuck. When his son, who has something of an inferiority complex with regards to the Commander's and Starbuck's relationship, asks if the Commander would have stayed so long if it had been him down there, Adama asserts that if it were him, they would never leave.
Deconstructed by George in Being Human, who grows paranoid for the safety of his daughter after his partner Nina is beaten to death by vampires, and constantly keeps watch over her crib without allowing her outdoors. Also a literal example, since George is a werewolf.
Josh is quickly becoming this as of Season 3 in the American remake. Which is hilarious considering he's no longer a werewolf.
Agent Booth from Bones won't hesitate to hurt or kill if anyone tried to get too close to Brennan. He is fiercely protective of her, escaping from the hospital despite his injuries in order to save her from a crazy ex-FBI agent.
Booth wasn't happy when Howard Epps escaped from prison. But when Epps got close to Booth's son Parker, he went full-on Papa Wolf.
He's also willing to give up a promotion, a raise and a trip to Hawaii to keep his little brother from being dishonourably discharged.
Not just once. He did the same thing to The Man Behind the Man. Said man behind the man was a Deputy Director of the FBI. Papa Keenan is both thorough and frighteningly unfettered when it comes to protecting his children.
Angel: Don't do that! Mayor: Oh, I will. I'll do worse! Murderous little fiend! Did you see what she did to myFaith?! Angel: I got no plans to weep over that. Mayor: Yeah, well, I'd get set for a world of weeping! I'd get set for a world of pain! Misery loves company young man, and I'm more than willing to share that with you and your whore!
In Burn Notice Michael Westen often accuses his little brother of being a ne'er-do-well. But when his little brother is in trouble he'll always stick up for him. It is notsafe to pick on Michael Westen's brother.
Several of Michael's clients are as well. One takes a beating and doesn't lose his cool because his son's being held hostage. Another, on seeing a con artist who sold fake medicine that made his son's health worse, jumps out of a car, chases the guy down and beats the crap out of him.
Rick Castle. You do not mess with his daughter. Not even if you are Mr. Macho Cool Slaughter, who can get away with saying plenty of risque things about Beckett (who Castle is normally quite protective of as well, if the situation calls for it. Not that the situation often calls for it) but earns a punch in the nose for even thinking about talking that way about his daughter.
Crops up again near the end of season 5 when Alexis is kidnapped. Castle successfully tries out the Jack Bauer Interrogation Technique on an injured man to get information. You don't see the actual violence, but the Tranquil Fury beforehand is truly terrifying.
In Charmed, Leo spent the first half of Season 6 in Papa Wolf mode after both his sons were put in danger.
All three detectives — Voight, Olinsky, and Dawson — on Chicago PD have shown their ability to become downright terrifying when their kids are in danger.
Aaron Hotchner of Criminal Minds is without a doubt Team Dad to the entire team. And he is not a dad you want to mess with. Although, considering his workaholic tendencies and his eventual divorce as a result, he's often a better dad to the team than he is to his actual son. He even plays Papa Wolf to children involved in their cases.
Hotch and Rossi's co-parental status is lampshaded when team super badass/older brother Derek Morgan asks, "Where's Mom and Dad?" to which team organizer/big sister JJ responds, "Hotch and Rossi are still at the conference." No mention of which is which, but it's worth noting that Hotch's status as Team Mom has been a running gag in fandom since season 1.
Hotch invoked this trope all over the recurring villain who came after his own family. Like Fin Tutuola, above, he wouldn't — and didn't — stop at "half".
On CSI: Crime Scene Investigation, Grissom (who is just about as mild-mannered as they come, and at this point had few moments in which he lost his temper) gave Catherine's abusive ex an Oh Crap moment by letting out a very loud "Hey!" and looking all the world like he was going to charge down the hallway when Eddie tried to bully her.
There's also this memorable rant, showing that you do not fuck around with kids on Gil Grissom's watch:
Gil Grissom: Let me tell you something, Humbert. You're twice the age of these kids, and half of them couldn't find their own ass with a map. You prey on innocent children, concocting God-knows-what from God-knows-where, selling Russian Roulette in a bottle and you think we came all the way out here to bust you for possession, you dumb punk? I'm gonna get you for murder. Cool?
D.B. in the season 12 opener. Grandpapa Wolf you could call it in that case. He kept enough control not to do anything stupid, but Brass still yelled at him during the search for his granddaughter.
ConradEcklie just kind of goes quiet and upset when his daughter, CSI Morgan Brody, gets into danger when their relationship is early in the healing stages. Once they truly repair there relationship and Morgan lets him in, this changes, as shown when Morgan is abducted by a serial killer after Ecklie allowed her to go undercover. He is supremely pissed, actually punching a suspect in the face despite being the sheriff.
The same probably also goes for Horatio Caine on CSI: Miami.
And Angela's dad as well.
Ditto with CSI NY's Mac Taylor...it's shown up several times with Lindsay in particular. In the ep where the lab was shot up, Mac crashed through his half broken office window to pull her out of the line of fire after she basically had a panic attack, apparently.
In Dexter, Dexter Morgan intentionally breaks his rules for the first time in order to protect his girlfriend's daughter from a pervert, despite not having any proof that the perv is a murderer. He even compares himself to a wolf directly in the Season 3 finale, as he prepares to smash the bones in his hand in order to make his escape from King, and live to be a father to his unborn son. In general, he seems to hold a particular antipathy for any of his victims who victimize children.
In Season 5 he beats the snot out of an abusive stepdad (whose stepdaughter was friends with Astor, Dexter's own stepdaughter) and runs him out of town, partly to help out the girl being abused, but also to ensure the abuser never goes near any member of Dexter's family.
In Season 6, Dexter considers lettint the police catch the Doomsday Killer, but then he kidnaps his son.
Diagnosis: Murder. Do not mess with anyone Mark Sloan has taken under his wing, or the kindly old doctor will destroy you. In one episode, the villain knocks Steve Sloan down a flight of cement stairs, while Mark is standing at the top. Mark immediately high-kicks the guy down those same stairs with an impressive . When asked if it was karate, he casually replies, "Fred Astaire."
Doctor Who: "You just killed someone I liked, and that is not a safe place to stand. I'm The Doctor and you're in the biggest library in the universe. Look me up."
Also "NO FORCE IN THE UNIVERSE CAN STOP ME NOW!" when Rose's face/consciousness is stolen in "The Idiot's Lantern." I think it's fairly safe to say that you just don't mess with the Doctor's companions. Ever.
It's not just the new series that has the Doctor going all Papa Wolf when his companions are endangered. The cliffhanger to episode 3 of "The Caves of Androzani" is exhibit A.
When finding Sarah strapped to a rock and tortured in "The Sontaran Experiment", the Doctor utterly blows his tactical righteous cool and starts swearing and trying to beat up the Sontaran leader. This does not go well for him, which he would've known if he weren't blinded by rage.
In the episode "Amy's Choice", the Dream Lord remarks on the Doctor's tendency to swell in masterful fury when someone he cares about is threatened.
Series 6 turns this Up to Eleven in its midseason finale, where the Doctor gathers a literal army to rescue Amy and her daughter. But this is outshone by Amy's husband Rory, who dons Roman centurion armor and a sword and fights his way through an entire Cyberman starship just to ask them a question:
Series 5, The Eleventh Doctor acts as a Papa Wolf for all of humanity to the Atraxi with a little history lesson in the first episode. Safe to say, his speech solidified Matt Smith as The Doctor for those who weren't already convinced.
Atraxi: You are not of this world. The Doctor: No, but I've put a lot of work into it. ... The Doctor: Okay! One more, just one more... is this world protected? *cue montage of aliens who have attacked or threatened humanity* The Doctor: But you're not the first lot to have come here. Oh, there have been so many! And what you've got to ask is... what happened to them? *cue montage of the previous ten incarnations of the Doctor, ending with Eleven stepping through the image of Ten* The Doctor: Hello. I'm the Doctor. Basically... run.
In "The Doctor's Wife," he is tricked into coming to House's asteroid by the dead message-boxes from Time Lords, causing him to despair that once again he's the Last of His Kind... and if that wasn't enough of an insult, all because this was a trick to distract him so that House could attempt to consume his TARDIS.
Doctor: You gave me hope and then you took it all away, thats enough to make anyone dangerous! God only knows what it will do to me! Basically... RUN!
Craig, previously shown to be an ineffectual loser who needed the Doctor's help to even ask a girl out, manages to resist being converted into a Cyberman and blows the Cybermen's emotional inhibitors when he hears his son crying.
From ER, we have a few doctors who would go to far lengths to protect their patients. Dr Kovac once yelled at a father for leaving his young daughter alone in the waiting room for some time while he was working, where there were druggies and other not-so-sane people around. Another time, when he suspected the husband of his patient was abusing her, he went to confront him and was fully willing to put himself in danger (hence getting punched as a result) to prove to the authorities that the guy was a danger to his wife and others.
Another time, Ray found out his ex-girlfriend had an abusive father. He helped her get away from him and when the father tried to catch the car, Ray flattened him with a punch.
Sheriff Jack Carter of Eureka. A nice guy who'd rather avoid nuclear anything, much less the radiation that comes with it. However, when his smart house goes crazy and targets his daughter, Zoe, with a destructo raygun, he breaks out his prized World Series autographed bat and wails on the house's nuclear generator in the hopes of knocking off the power... Which theoretically would have killed him and the five people trapped in the house with him. Sorry Boss, Best-Friend, Love Interest, and two mostly innocent bystanders, Jack's daughter ranks above all of you.
In a similar vein, Simon is this way with his long-suffering sister River. He's normally a relatively unassuming and actually quite timid doctor who isn't that good at combat, but when River is in danger, he goes all-out to protect her.
I wonder how many times Jubal Early has gotten slammed into a bulkhead by a 140 pounddoctor, shot him and then got knocked down by him again?
And while we're at it, don't hurt Kaylee. Jayne will make you pay if you hurt her. For that matter, so will Simon. And Mal. In fact, just don't hurt Kaylee. As Jubal Early can attest, it won't end well for you. Well, he could if he hadn't been shoved into the endless void of space.
Aaron Stark also qualifies. Don't try to hurt Tracy. Ever.
Ed Lane from Flashpoint is normally The Stoic but he is fiercely protective of his team, especially his closest friend Greg Parker. When he had enough suspicion that an investigator was specifically targeting Parker to ruin his career, he immediately went to warn Parker, breaking rules and even death-glaring a cop that stood between him and Parker.
Philip "Uncle Phil" Banks from The Fresh Prince of Bel-Air is known for his anger, but in the episode "Mistaken Identity," when a racist police officer arrests his son Carlton and nephew Will, he sees right through an obvious Engineered Public Confession. When said cop refuses to let them out of their cell, Uncle Phil unleashes a verbal ass-whoopin' the likes of which the poor bastard had never seen.
He also out-hustles a pool hustler who tried to cheat Will out of thousands of dollars!
Walter from Fringe was literally willing to destroy the fabric of the universe in order to save the parallel universe version of his son.
Eddard Stark in Game of Thrones. It's not only a pun on his House's sigil, the direwolf, but when his daughter Arya isn't brought to him first after Joffery gets mauled Ned shoves his way through the Lannister soldiers and even raises his voice at his king and best friend.
Despite the fact he doesn't get to see his daughter much, StannisBaratheon reacts with Tranquil Fury when his wife suggests beating his daughter Shireen. It's enough to make her immediately drop the subject.
Somewhat tragically, Jaime Lannister displays this when Joffrey is poisoned at his own wedding, shoving people out of the way to get to his son. Sadly (for Cersei and Jaime, anyway) it's too late.
Luke from Gilmore Girls, Rory's father figure, goes Papa Wolf quite a few times, one of these even leading to Lorelai proposing to him.
Glee: Kurt Hummel's dad Burt may not understand his son's obsession with musicals and dancing but when Kurt is refused a solo on the grounds of being of the wrong sex for it, he goes to the school and shouts at the principal and the teacher until Kurt is given a chance.
Papa Wolf status confirmed when he rips Finn a new one and throws him out of the house for calling Kurt a fag. Also a Crowning Moment Of Awesome.
Then there's what he's inches away from doing to Karofsky before Kurt pulls him off. Which is not too long after suffering a serious heart attack and week-long coma to boot...so, simply put? Do not mess with Kurt Hummel; you won't like the results. And he didn't even know the real reason Karofsky was threatening Kurt...
Danny "Danno" Williams in the Hawaii Five-0 reboot. Moving to the other side of the continent is the least he'll do for his daughter Gracie.
Half of the episode "E Malama" is basically Danny being this. Never endanger the life of his daughter.
Danny: If you ever bring a gun into the same zip code as my daughter again, I will put a bullet in your head.
In Heroes, the uber-example is Noah Bennet aka "Horn Rimmed Glasses/HRG", Claire's adoptive father. For one thing, when Claire Bennet was shot shortly after losing her powers (primarily to protect her dad), and was also slowly and painfully dying due to not having ever been sick in her life prior to this, he attempted to get revenge on Sylar by shooting him and went on a manhunt. His protectiveness of Claire Bennet and unwillingness to hurt her or let her get hurt was also what caused Claire to immediately deduce that the sniper who was gunning down the carnival members was not actually HRG, as the sniper managed to graze her in the arm, something that HRG would never have done even if he did attempt to gun down the carnival.
This is also true for Dr. Mohinder Suresh and Matt Parkman, the surrogate parents of Molly Walker. They're white hats, though, so they're not as extreme in their protective measures as Mama Bear Jessica or HRG.
Future!Sylar becomes a Papa Wolf. He's gone from a homicidal psychopath to a cuddly, waffle-making single father because he keeps his murderous instinct in check for his son's sake... and when said son in killed in the crossfire of a battle between Peter and the Company, Sylar literally goes nuclear and takes out the entire city.
With regard to Guerrero in Human Target — there is one man, a highly professional assassin, who mentioned his son once, and is still alive. There is a CIA boss who mentioned the danger the son might be in — he is not.
Admiral Chegwidden the Badass Team Dad on JAG, and even more fierce when his daughter Francesca is kidnapped by La Cosa Nostra. His response? Get a whole lot of ordinance from a navy ship and blow the hell out of the mobsters.
In Jekyll, Tom Jekyll and Hyde are both this in regards to Tom's family.
Kamen Riders Tendou Souji (Kamen Rider Kabuto) is a extreme case of this, insult him mock him he won't care. But if anyone - be they face stealing alien or human alike — threatens his sister in reality his cousin, but treats Juuka as his sister Hiyori is his Realy sister or Hiyori and he will beat you or if your said alien kick you into oblivion. A special note of this also goes to Kazama Daisuke (Kamen Rider Drake) and will go full on Papa Wolf if you even look at Gon in any way.
Law & Order: Special Victims Unit: Elliot Stabler's kids may as well be his Berserk Button; he once almost beat a pedophile half to death for posting pictures of his (underaged) daughter on an internet site. Then again, given that the only thing that keeps him doing that on a regular basis is that he can't use torture as a means to extract confessions, and once removed of that restriction, he quite gleefully beat into another suspect...
Odafin "Fin" Tutuola also counts: he points out that if it had been his kid, there would have been no "half" about it.
Often, a female victim's father learns the identity of the individual who hurt/killed his daughter, and he goes and takes his own revenge on the perp.
Dr. Cal Lightman of Lie to Me may be a Bunny Ears Deception Expert who has kind of a bad-boy vibe going on. But should you so much as threaten his daughter Emily (whether you're a punk kid or a cop or a federal agent), Cal will destroy you.
Should you happen to be in a coma, whether you're listening to Life On Mars or Ashes to Ashes don't mess with anyone under Gene Hunt's protection. Don't.
Little House on the Prairie: Several times, Charles playing watchdog over his daughters. More than once, Laura's husband-to-be, Almanzo, would be on the wrong end of Charles' wrath ... until Charles sees that "Manly" has pure motives. Indeed, Almanzo and Laura (despite their 10-year age difference) were a life-long couple, the (real-life) marriage ending only when Almanzo suffered a fatal heart attack in 1949, aged 92.
LOST: Ben, of all people, goes all Papa Wolf on Keamy's ass — but with disastrous consequences, and too late to do any good.
Very darkly used when Walt is taken away by the Others, and his father Michael not only betrays the group under their orders, but also kills Ana Lucia and Libby, all while attempting to protect his son.
A non-parental example on the same show is Merlin toward Arthur and Guinevere. A memorable scene in season three is Merlin telling Morgana in no uncertain terms that if she dares hurt either of them, she'll be going down hard. And she does.
In The Middle Mike has this towards his children; especially towards his daughter, Sue. An example of this would be in Season 1's "Valentine's Day".
Despite Modern Family's Cameron being overly dramatic and somewhat effeminate, when he thinks there's a stranger in Baby Lily's room he jumps out of bed, grabs a baseball bat, and charges in with a Pre Ass Kicking One Liner.
Mr. Belvedere: Not only did George play this with Heather once, he also got to play it with youngest son, Wesley, on one occasion:
The time with Wesley came in the memorable 1988 episode "The Counselor," where Wesley reveals that his camp counselor had attempted to molest him. The scene ends with George (along with Mr. Belvedere and Marsha) closing in on the creepy counselor as it is apparent he's trying to bluff an explanation, dissolving into a scene where Mr. Belvedere and Wesley return from talking to the police and George and Marsha comfort their son. (As it turns out, he's shaken but admits he's more interested in getting back to pulling pranks on the girls.)
Heather had her Papa Wolf protect her in the 1989 episode "Homecoming," where her homecoming date, Keith, a popular jock and the school's football star, tries to rape her in his car while the two are parked at a Makeout Point type destination. George – a sportscaster and huge sports nut – is buddies with Keith, and is naturally enthused by his athletic abilities and even wants to do a feature on him and all the college offers he's getting. Needless to say, that all changes when Heather reveals that Keith (who is at the Owens' and looking through George's sports memorabilia) tried to rape her; Mr. Belvedere, who found Heather's torn dress in an attic trunk while doing some cleaning and got Heather to reveal what happened, hints to George that something very bad happened. Once the truth is spilled, George asks Heather to leave the room, quickly grabs Keith by the shoulder, angrily tells him that he's a loser, kicks him out and then warns him never to come near his family again or else he'll regret it.
Leroy Jethro Gibbs WILL hunt you down if you ever harm his team or Forensic Specialist Abby... not that she usually needs rescuing. He has aggressively enforced this before, and at one point allowed a murderous drug dealer who had threatened Tony, Ziva, and McGee to be shot by the latter's people.
Gibbs' own backstory involves him hunting down and executing the Mexican drug lord responsible for the death of his first wife and their daughter.
In the episode "Twisted Sister", McGee goes Papa Wolf in his effort to clear his little sister.
Sniper Gibbs shoots a terrorist holding Ziva captive in a Somalian prison, from 1,000 yards, in the seventh season episode "Truth or Consequences". Ziva's partners Tony DiNozzo and Tim McGee deliberately allow themselves to be captured and interrogated to give Gibbs a chance to set up the shot and rescue Ziva. In the seventh season episode "Good Cop, Bad Cop," Gibbs sends a message to Ziva's father, the Mossad director, who sent her on a suicide mission and then left her to die in Somalia, that "She is off limits!" No one messes with Ziva on Gibbs' watch.
In the fifth season episode "Requiem," Gibbs beats up a man who is harassing his dead daughter's childhood best friend, Maddie Tyler, and later rescues her from her kidnappers.
In one episode there is a Flashback in which young Gibbs is in a fight with a bully and his dad comes out and fires a shotgun in the air. Which would indicate that it's In the Blood.
In Noah's Arc, Ricky actually fits in this regards to Noah at times, despite not being his father. Ricky introduced Noah to much of the gay scene, and shows increasing protectiveness of him as the series goes on, doubling as a friend and mentor at times. Whenever he feels Noah is in danger, he immediately goes into Papa Wolf mode.
In The Office, Stanley goes after Ryan pretty hard when he thinks he may be "sniffing around" his daughter.
Rumpelstiltskin of Once Upon a Time, especially before he gets his powers: a friendless cripple whose wife ran out on him years ago, his son is the only thing he's got left, and if you threaten that son, he will happily burn down his duke's palace, kill an evil wizard to usurp his powers, and then merrily kill every soldier he gets his hands on. He's also shown displaying Papa Wolf-ish tendencies towards other people's children — he speaks of wanting to protect all the children who've been conscripted to war, not just his son, and is visibly angered by Cinderella's casual offer to sell her other child.
Prince Charming as well. He fought of several guards in the pilot episode with only one hand while he carried his newborn daughter in the other, and in season two he bursts into Regina's home, sword in hand, and demands she hand over his grandson.
Touch Henry (or even put him in harm's way) and Regina and Emma, who did not really get along in Series 1 and parts of Series 2, will hunt you down and make you regret putting their child in danger and heaven help you if you kill Henry, for Regina will unleash seven bells of hell on you.
When she is willing to do anything, even put herself in danger for Henry when she does not have a heart anymore just shows how much she loves her child. Simply put: Henry = NO TOUCHY!... unless you want to die, in which case, go right ahead!
Harm an innocent child, namely Roland, Robin Hood's son, for being in the way... and Regina will alter your entire physiology in return.
Dan Scott on One Tree Hill may be a Jerk Ass, but try to hurt Lucas or Nathan, and you WILL be sorry, the best example is when he saves Nathan from a gang of russian mobsters.
Only Fools and Horses; a womanizing, chain smoking, gambling, borderline alcoholic who has at various points in his life bribed officials, sold both stolen and smuggled goods and is guilty of both tax and VAT fraud on a massive scale. But if you ever try and threaten his family — Del will be unhappy.
Cruelly subverted in Oz. When Vern Schillinger's son Andrew arrives in Oz, Tobias Beecher, Ryan O'Reily and Chris Keller seize the opportunity to get even with Vern. They help Andrew kick his drug addiction while implying to Vern that it's all a ploy to make Andrew their prag. Vern tries to warn Andrew, but it backfires. Vern eventually concludes that he'd rather kill Andrew himself than to see him subjected to a Fate Worse than Death. When the trio hears of Andrew's death, they just quip: "It worked."
Scorpius, the original Big Bad of Power Rangers Lost Galaxy goes on a rampage when he thinks the Rangers have kidnapped his daughter Trakeena. It ends badly for all involved.
In Power Rangers Dino Thunder, Tommy does not take kindly to his students being threatened. In one episode, Zeltrax taunting him with their deaths results in Tommy seriously wounding the cyborg.
A very literal example is Leanbow in Power Rangers Mystic Force given that he is the Wolf Knight, when he becomes the red Wolf Warrior, he protects his son and his friends in a truly awesome battle. The same largely applies to his counterpart from Mahou Sentai Magiranger, save that all the core rangers are his children in that version.
Prison Break: Linc to his son LJ, Michael to his nephew LJ. Alex to his son.
Linc, who is ready to tear Alex apart at the first opportunity, in season four finds out Alex's son is dead... and not only buries the hatchet but promises to help him go after the people responsible.
Psych: Henry may find his son a disappointment and isn't even afraid to admit it to Shawn, and can't even tell him that he loves him, he still has his Papa Wolf moments in cases where Shawn is in danger. Everyone loves a good concerned!Henry fic. 'Shawn takes a shot in the dark' anyone?
Raising Hope: Burt Chance loves his family. When his rock hero insults his wife, son, and granddaughter all at once, he gives the jerk a guitar to the back of the noggin. He even got a youtube mix out of it!
In Rizzoli & Isles, Maura Isles' biological father Paddy Doyle stabbed a rival mobster in the heart with an icepick to prevent him from killing Maura the way he'd already killed Doyle's son. On the dead man's chest was a blood-stained photo of Doyle holding Maura as a baby, pinned there with the icepick. Doyle's message: "Don't mess with my family." Doyle told Maura to call him with the murderer's name and he'd "send the man a message" but Maura couldn't do it, even if it meant she would be murdered. It's strongly implied that another Papa Wolf, Jane Rizzoli's ex-partner Vince Korsak, called Doyle to protect Maura.
Ray Campbell in Sister Sister had one of these moments when the twin daughters (well, technically Tamera only, Tia only went after it became apparent that Tamera snuck out of the house in an attempt to get her back home, but her plan ended up backfiring) attempted to meet Verique, who despite his identity on the web, was actually a sex offender who often lures women into posing for dirty pictures. As soon as Ray and Lisa found this out (as well as where he lives due to directions), after the twins attempt to escape but fail, Ray and Lisa appear behind him and, in a Crowning Moment of Awesome, punches Verique in the face after Lisa shouts "What's love got to do with it, ya punk?!"
Clark Kent on Smallville, whenever children are in harm's way. Also Jonathan Kent and later on, Lionel Luthor.
Jonathan Kent was actually pretty legendary in this regard. One memorable scene was when Lionel tried to blackmail him again, or he'll expose Clark's secret to the world. He chose to beat seven shades of crap out of Lionel, nearly killing him, until he was struck with a heart attack, and died. He literally sacrificed his life to protect his adopted son.
Granted, the situation was not quite what he thought it was (Lionel was actually on the way to a Heel-Face Turn at this time, and himself took Clark's secret to the grave 2 Seasons later), but given Jonathan's history with the Luthor family, his overreaction is understandable (and Lionel even admitted his fault in Jonathan's death).
Floyd Henderson in Smart Guy doesn't actually get a chance to demonstrate his Papa Wolf potential, but in the episode Strangers on the Net, after TJ admitted to Floyd that a man posed as a kid on a kid's chatroom and later has the guy arrested (who also turned out to have been arrested for this sort of thing before and placed on prohibation), and was unlikely to be getting out of jail anytime soon due to breaking prohibation, Floyd remarks "Lucky for him" when hearing this, implying that he intended to do far worse to him as soon as he got out.
Tony Soprano may not be the most morally upstanding of men, but one of his most consistently humanizing features is his sincere love for his children, Meadow and AJ. They may not always get along with their dad, but god help you if you insult, harass or endanger them. Additionally, one of the most heart-wrenching scenes in the series is Tony's soliloquy in Dr. Melfi's office when he concludes that AJ has inherited his depression.
Stargate SG-1: General Hammond is usually the level-headed, occasionally obstinate commander of Stargate Command. But when you threaten his people (especially SG-1), you'd better run.
When SG-1 was captured by a System Lord, he sent four teams to rescue them, and when they were captured as well and his superiors ordered him not to risk another rescue mission, he went offworld to gather help to rescue them himself. He and Teal'c end up piloting a fighter through the damn Stargate, while Hammond shows his Texan heritage with a hearty "Yeehaw!"
When SG-1 was sent back to 1969 in a freak accident, Hammond sent a note with them, which said only "Help them." His thirty-years-younger self found the note and indeed decided to help SG-1 escape custody, solely on the basis of recognizing his own handwriting.
When SG-1 was nearly killed while trying to uncover an Ancient weapon to save the planet, it was Hammond who saved them at the last minute, by personally taking command of Earth's lone spaceship and giving them enough time to save the world...again.
In Star Trek: The Next Generation, Worf occasionally shows Papa Wolf tendencies for crew members serving in his department. Despite being a superior officer and having previously admitted that Data is capable of easily overpowering him, Worf still warns him against abusing Lt. D'Sora, who had shown romantic interest in him. Data, however, is oblivious to Worf's implied threat:
Worf ...However, Lieutenant D'Sora serves under my command. If she were mistreated, I would be very displeased—(Beat)—Sir.
Star Trek: Deep Space Nine: Both Quark and Rom are this to Nog. Rom went so far as to threaten to burn the bar when Quark tampered with Nog's examinations for Starfleet Academy. Despite appearances, Quark was also fiercely protective of Nog, going so far as to gun down Jem'Hadar for him.
Step by Step: Frank was often the bumbling dad, much to the chagrin of eldest stepdaughter Dana ... especially when his attempts to play Papa Wolf result in (comical) failure. However, by the final act, when Frank plays things straight ... he is a very effective in warding off boys with undesirable ulterior motives. He never did this too much for younger stepdaughter Karen, as most of the sitcom dynamic was reserved for Dana's distaste with Frank. However, toward the end of the series, Frank played Papa Wolf for Al.
Even though he'll chew Cas out for ditching them at weeks at a time and doesn't seem to concerned when the man starts bleeding from the face, he's been known to blast an angel or two (or four, or ten, or -) back to Heaven for messing with Cas.
Actually, John has frequently shown a reluctance to put his boys in danger and even wasted one of the Colt's precious bullets to kill a vampire that was threatening Sammy. Even after he was dead, he climbed out of hell to kick Azazel's ass when he attacked the boys. If anything, John transforms from a Bad Ass to the incarnation of the Wrath of God when Dean or Sam are in trouble.
There's also the fact that he sold his soul and the only weapon that could kill Azazel (who he'd spent the past 20 something years hunting) to Azazel to make sure Dean would live. The man may not be the most stellar father, but it can't be denied that he does try.
A man named Jimmy Novak is dying, and then is told that his daughter Claire will be the vessel for the angel Castiel. He demands that Castiel use him and spare poor Claire the trauma of seeing everything Castiel has to do, even though it means he'll never see his family again. Castiel accepts, and Jimmy becomes the Soul Jar of sorts for him and the Cas we know.
While Bobby is a Parental Substitute and not the boys' actual father, he very much embodies this for them.
Mr Argent from Teen Wolf. Except he wants to protect his daughter FROM an actual werewolf.
Hehe, Papa "Wolf".
And Sheriff Stilinski will not hesitate to pistol whip anyone who's stupid enough to hurt his son.
In Tin Man Wyatt Cain beats up, shoots or threatens anyone who comes within an arm's length of DG. Don't hurt the Princess.
Torchwood: Team Dad Captain Jack Harkness fits this whenever his team is put in danger... especially when it's perceived to be his fault (directly or not). All you have to see is him charging in to save his team with swishing coat and one heck of a gun in "Countrycide" to realize that you don't mess with Torchwood.
Somewhat subverted in Children of Earth when Jack sacrifices his own grandson to save millions of other children.
From Miracle Day: Known murderer and paedophile Oswald Danes is in Gwen and Rhys' house and makes the mistake of laying a hand on their daughter. Rhys spends the remainder of the episode threatening to kill him. Danes even notes at one point that Rhys would probably do it.
Silver in the recent Treasure Island adaptation on Sky 1. He risks a lot to keep Jim safe, and when Squire Trelawney pulls a sword on Jim at the end, Silver disarms him with only his crutch — while chained to the helm — and threatens to kill him if he does it again.
Bonnie from The Vampire Diaries uses a spell to put Luka in a trance and get some information. Afterwards, Luka doesn't remember what happened but suspects Bonnie of doing something to him. His father Jonas marches into Jeremy's house to find Bonnie, grabs her around the throat and takes away her powers.
Keith Mars, who previously gave off the impression of a Non-Action Guy, goes berserk when the first season's villain tries to burn Veronica alive. He even walks straight through the fire to save his daughter, spending several weeks in a hospital afterwards.
The domineering, abusive and murderous Aaron Echolls seems oblivious that his daughter is being beaten up by her boyfriend, even appearing interested in starring in a movie he wants to pitch. However, at the start of what looked to be a pleasant dinner he administers one of the most comprehensive beatdowns ever seen on TV, before calmly concluding "I've decided I'm not interested in appearing in your movie." It would appear that the same protectiveness doesn't apply to Logan, though.
In the The Walking Dead, Rick Grimes is usually a Nice Guy who's main goal is to provide for the people under his care, be they friends, family, or even strangers. However, there's almost nothing he won't do if he feels his family is being threatened, though even then he'll first try reason.
In the Season 4 finale, when the Marauders corner Rick, Michonne, and Carl on the way to Terminus and threaten to viciously rape the latter two while also beating Daryl to death, Rick goes absolutely ballistic and literally tears Joe's throat out. With his teeth. And then he viciously guts the pedophile who was attempting to rape his son. The latter's Oh Crap expression at what Rick had done is especially satisfying...
The West Wing. President Bartlett had a very memorable rant about what would happen if something happened to his daughter Zoey, calling it "the nightmare scenario", since "this country no longer has a commander-in-chief but has a father who's out of his mind because his little girl is in a shack somewhere in Ugandawith a gun to her head!"
Played straight on several other occasions, notably when Bartlet believes a reporter has approached his daughter Ellie despite strict rules forbidding them to do this.
Toby is also a straight example before his children are even born:
Toby: I'm told that on my sunniest of days I'm not that fun to be around. I wonder what's going to happen when you make my children a part of your life.
In the episode "The Stackhouse Filibuster" when the White House figures out that Stackhouse is doing this for his grandchild, the entire mood of the episode changes. Suddenly, no one thinks he's going to back down anytime soon, because the power of parents and grandparents is well known.