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.
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.
Leanbow in Power Rangers Mystic Force. 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.
Keith Mars, Veronica's private detective and formerly the town sheriff, goes berserk when first season's villain tries to burn Veronica alive.
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.
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.
A number of the female victims father found out that someone had killed his daughter and went out and killed the perp.
Ace Lightning's Simon Hollander is a mild mannered accountant - until you insult his son.
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. I submit the cliffhanger to Episode 3 of the Caves of Androzani as 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 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 a 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, this 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 The Eleventh stepping through the image of The Tenth* The Doctor: Hello. I'm The Doctor. Basically... run.
In The Doctor's Wife where 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!
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.
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 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.
Phillip "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, and 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.
Another example of Uncle Phil's Papa Wolf badassery is when the parents of Ashley's school bully advise that they seek psychiatric help for her. Long story short, shit gets real.
He also out-hustles a pool hustler who tried to cheat Will out of thousands of dollars!
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 goes nuclear and takes out the city.
Lampshaded on Angel: 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.
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.
In Battlestar Galactica, Commander Adama has repeatedly referred to his crew as a family and came 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.
LOST: 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.
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!
Aaron Stark also qualifies. Don't try to hurt Tracy. Ever.
Jack Bristow of Alias is an Action Dad extraordinaire for his Action Girl daughter Sydney, despite being absent for much of her life due to his job with the CIA.
Aaron Hotchner of Criminal Minds. 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.
In Charmed, Leo spent the first half of season 6 in Papa Wolf mode after both his sons were put in danger.
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
In one episode of NCIS 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.
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.
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."
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 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.
Actually, John has frequently shown a reluctance to put his boys in danger and 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.
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 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.
On CSI, Grissom (who is 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.
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 had a panic attack, apparently.
The same probably also goes for Horatio Caine on CSI: Miami.
And Angela's dad as well.
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.
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.
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...
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.
Psych: Henry has his moments in cases where Shawn is in danger. 'Shawn takes a shot in the dark' anyone?
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.
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.
Jonathan Kent on Smallville 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 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).
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.
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!
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.
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.
Ray Campbell in Sister Sister. He had a Papa Wolf moment 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?!"
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.
Walter from Fringe was willing to destroy the fabric of the universe in order to save the parallel universe version of his son.
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.
Breaking Bad: Walt White is not too fond of people making fun of or hurting Walt Jr. or Jesse. If you do either of those, prepare to PAY for it, and pay it dearly.
That said, he's perfectly willing to hurt Jesse himself.
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.
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.
In Andromeda threatening a Nietzschean's wives and children is one of the easiest ways to get them mad at you. This is part of their Social Darwinist values, they are trying to preserve their genes.
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.
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.
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.
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 was one of the undercover workers - and she nearly got food poisoning from food prepared by a chef who didn't wash her hands after handling raw chicken. John broke his own protocol and called off the undercover stint, tore into the bar to stop her from eating the food, and then went into the kitchen, where he gave the chef possibly the most vicious dressing-down in the history of the show.