Of all the entertainment tropes, one-liners are among the coolest. Coining a catchy sendoff before a decisive action solidifies a character as someone who shouldn't be messed with. This is not only fun, but it can also enhance the fear factor. These moments mainly exist in blockbuster action flicks, but the small screen sometimes proves just as capable of carrying a catchy line.

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These moments are arguably more frightening, because audiences have more time to ruminate on them. With such cold-hearted characters in the mix, every episode is fraught with uncertainty. These one-liners scared viewers senseless yet forced them to continue watching.

9 "Save Yourself. Kill Them All." — Hannibal

Hannibal Lecter and Francis Dolarhyde in Hannibal

Once this twisted TV show started adapting Red Dragon, it was only natural to pull lines straight from Thomas Harris's novels. Secretly communicating with the imprisoned Hannibal Lecter, fellow serial killer Francis Dolarhyde struggles with the sacrifices demanded by the Great Red Dragon (his murderous other half). The doctor proposes that he target friend Will Graham, informing the maniac that the criminal profiler has a family. He then implores Dolarhyde to save himself by killing them all.

This line hammers home the mentality of this erratic murderer. He needs to wipe out entire families to keep his more dominant persona from hurting him. Moreover, it shows the lengths to which Hannibal will go, in order to isolate Will from everyone else. Without pesky positive influences, the reluctant hero with a killer mindset will be easier to mold to his fullest potential.

8 "How The Little Piggies Will Grunt When They Hear How The Old Boar Suffered." — Vikings

Ragnar Lothbrok in Vikings

Not many people achieve vengeance from beyond the grave, but Ragnar Lothbrok does it perfectly and forever carves his name into Norse legend. The aging Viking aims to resolve unfinished business. Last on his list is retribution for a past betrayal: the Saxon slaughter of a Scandinavian settlement in England. Sadly, Ragnar's fellow warriors have lost faith in him as a leader, but his sons are esteemed figures by this point. As such, he allows himself to be captured and executed, uttering this line before ascending to Valhalla.

It seems silly, but it proves a deadly warning. The Ragnarssons amass a vast army and ravage the English kingdoms. In killing those responsible, they gain revenge for both their father and the settlers. As if on cue, Ragnar's words echo through the following episodes. Viewers know he's watching from the afterlife and laughing.

7 "Did You Miss Me?" — Sherlock

Jim Moriarty in Sherlock

Whether on the big or small screen, Sherlock Homesstories have always struggled to come up with villains as engrossing as Moriarty. The creators of this BBC show probably knew that. After killing off the detective's nemesis in Series 2, they later hit fans with this eerie tease. Screens across the country go dark before broadcasting the villain's sneering mug. Though he doesn't speak himself, a computerized voice repeatedly asks, "Did you miss me?"

Viewers and characters alike are instantly filled with questions. Is Moriarty really back? How did he survive a gun to the head? What scheme does he have up his sleeve this time? Equal parts haunting and humorous, the madman's message promises more cheeky mysteries in the future.

6 "Don't F*** With The Peaky Blinders." — Peaky Blinders

The Shelby family in Peaky Blinders

Several variations of this line pop up throughout the show, but the idea remains the same. Forged through family and hardship, the eponymous Peaky Blinders are the toughest, craftiest gang around. Thus, their enemies ought to know who beat them, and who will do it again if they step out of line.

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This is why the characters often dish this mantra out after their victories. Arthur, John, and other lieutenants shout it whenever they muscle into a new territory or beat someone down, and Polly whispers it as she kills the sadistic Inspector Campbell. It's a simple yet satisfying sendoff. More than the words themselves, this creates a clear message that the Peaky Blinders don't make idle threats.

5 "The North Remembers." — Game Of Thrones

Arya Stark and Walder Frey in Game of Thrones

The Northern characters in Game of Thrones constantly emphasize that "winter is coming," but the more affecting phrase has to do with personal retribution. This simple line means it's natural for the lordship and custody of the North to be a certain way. No matter who attempts a hostile takeover or betrayal, things will always return to this status quo, through bloodshed if necessary. It's mainly a rallying cry, but Arya Stark uses it to justify a mass execution.

After witnessing Walder Frey kill her brother, mother, and the entire Stark army, Arya slits the old man's throat and poisons everyone in his feasting hall. She then leaves with "The North Remembers." Though minimal, this line provides immense satisfaction for those devastated by the Red Wedding. From this point on, other factions will think twice about crossing the Starks.

4 "We Were Never That Good." — Strike Back

Damian Scott and Michael Stonebridge in Strike Back

Scott and Stonebridge go out on a high note in Strike Back. Cornered by mercenaries paid by Whitehall to tie up loose ends, the two counterterrorism operatives meet with the leader of their assailants. He offers to spare them for a bribe. They refuse, and he says that they always lost out due to being "too good." Stonebridge counters, "We were never that good," and blows the merc away.

This reaffirms what viewers have seen countless times before: these two do whatever it takes to complete the mission and survive. Spitting in the face of classic hero tropes, they're whatever they need to be to win.

3 "No, But Why Speak Ill Of The Dead?" — Justice League Unlimited

Lex Luthor and Gorilla Grodd in Justice League Unlimited

The DC Animated Universe often gives fans the best iterations of their favorite comic characters, and that's certainly the case for Lex Luthor. He's willing to do whatever it takes for greater power, and he delights in outsmarting enemies in this pursuit. One would think he'd find common ground with fellow evil genius Gorilla Grodd, but the universe just isn't big enough for the two of them.

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Luthor says as much when they battle for leadership of the Legion of Doom. He tricks the ape into an airlock and offers some final words for his enemy. He proposes that things could have gone down differently between them. Grodd agrees, but Luthor retracts his praise, saying that he preferred not to speak ill of the dead. With this insult, he opens the doors and jettisons the gorilla into space. Aside from the action star appeal, this line perfectly encapsulates Luthor's incorrigible and cold-blooded narcissism. Such blatant disrespect is not only amusing, but also reinforces the character's uncompromising nature.

2 "No One's Ever Safe." — Terminator: The Sarah Connor Chronicles

Sarah and John in Terminator: The Sarah Connor Chronicles

This TV series directly follows Terminator 2, which means Sarah Connor and her son, John, supposedly prevented the nuclear apocalypse and war against the machines. Theoretically, they can rest easy. After spending half her life fighting, though, Sarah can't drop her guard. She always feels the need to prepare for another attack. Hence, this warning returns at the end of the pilot. After establishing a hideout for their renewed fight against the time-traveling robots, Cameron assures John and Sarah that they're safe. Mother and son alike assert that "no one's ever safe."

Such a sentiment echoes the fear permeating the whole series. A catastrophic war is predestined, so most people in the present will die horribly in the coming years. More poignant is what that fear has done to the characters. They never feel secure, and thus, can't experience any lasting happiness. It's grim, but that atmosphere is one of the most engrossing elements of the Terminator mythos.

1 "This Is It. This Is All We Are." — The Knick

John Thackery in The Knick

Early 20th-century surgeon Dr. John Thackery is notorious among the medical community, repeatedly taking big risks yet often yields big rewards. Sadly, he suffers a series of setbacks, with the final straw being the loss of his lady love due to surgical complications. The unhinged Thackery performs a cancer removal procedure on himself. Surprise, surprise — it goes wrong. As the surgeon's body shuts down, he laments to his fellow doctors that "this is all we are."

Medicine is perhaps the most important field in the world; doctors hold people's lives in their hands. That said, it often results in ugliness and loss. Experiencing these daily is enough to break anyone, but Thackery was different. He would always return from setbacks with renewed zest and a solution. For him to not only fail, but lose faith in the practice, shows how demoralizing that practice can be, especially during this time period. With so much death, it's a wonder how any doctors kept going.

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