For other uses of "Killer Frost", see Killer Frost (disambiguation).
"If you knew me at all, you would know that I hate the name Caitlin. I'm Killer Frost!"
—Caitlin to Barry Allen[src]

Caitlin Snow (died April 2016), better known as Killer Frost, was a meta-human from Earth Two with the ability to unleash frozen air from her hands. She was also the wife of the late Ronnie Raymond. She was formerly an ally of Zoom and a former reluctant ally of Team Flash.


Early Life

Caitlin once had a brother named Charlie, who died, leaving her mother "cold". She later went to medical school, but rarely studied and flunked out and had to move back in with her mother.[1] At one point in her life, Caitlin met and married Ronnie Raymond. Around 2013, Caitlin and Ronnie were affected by Harrison Wells' S.T.A.R. Labs particle accelerator, giving her cryokinetic abilities and him pyrokinetic abilities. Since then, Caitlin cut off all ties to her past life and began calling herself "Killer Frost" and refused to use her real name. Even so much as hearing it made her angry.[2]

The arrival of Earth One Flash

Deathstorm and Killer Frost kiss

Caitlin and Ronnie kiss.

After Francisco Ramon/Reverb vibed that his doppelgänger, along with other Earth One residents, had arrived on Earth Two, Caitlin and Ronnie searched for them. The two went to Jitterbugs and asked everyone which one of them were in the wrong universe. When Barry called her Caitlin, she told him she no longer went by that name. Caitlin then fired icicles toward Barry, who used a table as a shield. After Ronnie critically injures Joseph West, Caitlin and Ronnie were brought outside while Iris was distracted. After failing to kill Barry, Caitlin told her husband to do the job. The Flash used a helmet from a statue of Jay Garrick to redirect fire hurled by Ronnie toward Caitlin and badly injured her, and she was taken away and tended to by Ronnie.

Killer Frost and Deathstorm

Killer Frost and Deathstorm confront Iris, Lawton and Vibe.

Later, Caitlin and Ronnie were approached by Iris, Floyd Lawton, and Cisco Ramon/Vibe, Reverb's doppelgänger, though she and Ronnie made the three stand their weapons down. When Reverb tried to get Vibe to join him, the Flash intervened. The Flash was eventually overpowered by both Reverb and Ronnie but Caitlin warned them that Zoom told them to make sure the Flash was left unharmed. Zoom arrived and killed Ronnie and Reverb, much to Killer Frost's horror. She was approached by Zoom but was told the latter was happy one of them knew their place. After Zoom sped off, Caitlin ran toward her husband's body but soon ran away in grief.[2]

Cisco holds Killer Frost at gunpoint

Caitlin is held at gunpoint by Cisco.

After Ronnie's death Caitlin fled into the woods to mourn but was soon approached by Iris, Harry, Cisco/Vibe, and Earth Two Barry, demanding to know where Zoom was but she refused to tell him. Instead Caitlin tried to kill them and bring them to Zoom but Cisco eventually held her at gunpoint and Caitlin surrendered. However she still refused to tell them where Zoom was and Cisco tried to reason with her, telling Caitlin of her Earth One counterpart and how distraught she was when her Ronnie died too. Upon hearing this Caitlin was convinced to aid them and took them to Zoom's lair.

Caitlin attacks Zoom

Caitlin attacks Zoom.

Though Caitlin freed Jesse she was unable to free Earth One Barry since she wasn't able to penetrate the carbine glass, but Barry eventually managed to phase his way out on his own. However Caitlin has secretly called Zoom and he showed up as soon as Earth One Barry escaped. However when Zoom told them all that though he couldn't kill Earth One Barry or Harry he could kill everyone else, and started with Jesse. However before Zoom could kill her, Caitlin turned on Zoom and blasted him with her ice powers, and held him down long enough for everyone else to escape.[3] She was then imprisoned in Barry's carbine cell as as a reminder of her Earth One counterpart, whom Zoom had feelings for.[1]


Zoom kills Killer Frost

Zoom kills Caitlin.

After a couple months, Caitlin was annoyed by her fellow inmate with an iron mask but wasn't sure why she was even still alive. It wasn't until Zoom brought her doppelgänger that Caitlin realized she was spared because she is the Earth Two version of the woman he loves, and began plotting her escape. However, Caitlin always intended on killing her doppelgänger, both as revenge on Zoom and the fact that he wouldn't need her anymore. When seen by Earth One Caitlin, they introduced themselves. Caitlin compromised that if Earth One Caitlin freed her, she will lead her to her Earth. While working, both Caitlin's talked of their very different lives, but found common ground in their shared dislike for their mothers. Earth One Caitlin eventually found a way to weaken the carbine enough for Caitlin to able to escape. As Earth One Caitlin wondered what to do about the man in the mask, Caitlin tried to kill her. Earth One Caitlin tried to flee but Caitlin used her powers to create a sheet of ice, causing her to slip and fall. As Caitlin was about kill her doppelgänger with an icicle projectile, Zoom intervened and took the icicle from mid-air and brutally stabbed Caitlin in the stomach, confirming that he doesn't need her anymore. Zoom dropped Caitlin's body to the ground, leaving her to die.[1]


In order to keep Black Siren occupied, Earth One Caitlin and Cisco dressed up as their Earth Two doppelgängers and tried to convince her to join them, though Black Siren soon saw through the ruse.[4]

After the dissolution of the Flashpoint timeline, Earth One Caitlin gained the same powers as her doppelgänger as well as a split personality and was worried she would become evil.[5][6][7]

Caitlin (Earth Two) was avenged one year later, when Caitlin (Earth One) kills Zoom become Black Flash when he tried to kill Savitar.

Eventually though, Caitlin was able to come to terms with her Killer Frost side, allowing them to coexist.


Unlike her Earth One counterpart, who is compassionate and loving, Caitlin was cold, cruel, sadistic, ruthless, arrogant and immoral with no guilt or remorse for the deeds she committed as Zoom's enforcer. Despite these negative traits of hers, Caitlin genuinely loved her husband, Ronnie Raymond. She even became turned on when witnessing Ronnie in battle.

Caitlin has a fairly uninhibited personality, being public in her affection for her husband. She enjoys showing off her body and even poked fun at Earth One Caitlin's more modest clothing.

Underneath her arrogance. Caitlin was openly terrified of Zoom; unlike Ronnie and Francisco Ramon, she knew better than to disobey his orders as the latter would have killed her for trying to harm the Flash.

After Zoom murdered Ronnie, Caitlin was devastated and heartbroken. She desired revenge on Zoom, being willing to briefly ally with Team Flash to help free the Flash and Jesse Wells, the speedster's prisoners, regardless of the potential risks. Caitlin's desire for revenge soon grew beyond reason; she tried to murder her doppelgänger, who Zoom loved, as revenge for what happened to her husband despite the fact that Earth One Caitlin helped the former escape from her cell.

Powers and abilities


  • Meta-human physiology: After Caitlin was struck by the energy of the Particle Accelerator explosion on Earth Two, this altered her DNA and supercharged her cells, augmenting her physiology to properly access her newfound powers.
    • Cryokinesis: Caitlin had the ability to freeze air around her hands and form it into icicles or other sharp objects. Caitlin was also capable of creating objects such as a bridge by shooting ice from her hands. She could also freeze an entire human body with just a kiss.[2].


  • Skilled tactician/Manipulator: As an enforcer for Zoom, Caitlin was a capable tactician and manipulator.
  • Medical knowledge: Despite failing medical school, Caitlin has shown to have some knowledge in medicine.


  • Carbine: Caitlin's cryokinesis had no effect on this compound.
  • Limited control: It is implied that Caitlin could not control her powers upon contact with others, thus limiting her to only being able to kiss people with extreme body temperatures such as her late husband.


  • Killer Frost suit: Caitlin wore a suit as her villainous alter-ego, Killer Frost. The suit consists of black and blue leather clothing to match Caitlin's personality and her cold powers.


The Flash

Season 1

Season 2

Season 3

The Chronicles of Cisco


Promotional images

The Flash

Season 2


  • Since Earth One Caitlin specifically stated in "King Shark" that she does not possess the metahuman gene, the fact that Caitlin of Earth Two was able to become a metahuman is the first indication that there are more subtle differences beyond contrasting events.
    • This detail is implied to be one of the many changes following Flashpoint, as Earth-One Caitlin has manifested her counterpart's powers after Barry altered the timeline.
  • Unlike her Earth One counterpart, Caitlin is more willing to show off her body and even poked fun at her doppelgänger's choice in clothes. However, after Caitlin got powers, her Killer Frost side changed clothes in front of Iris, Felicity and Cecille, implying that it's only the Frost persona in both versions of Caitlin who doesn't like to dress modestly.
  • Apparently, Caitlin Snow doesn't exist on Supergirl's Earth. However, as shown by Jay Garrick being Henry Allen from Earth Three, same versions of people do not necessarily have the same name.
  • Caitlin and Ronnie's song is "My Funny Valentine."[2]

Behind the scenes

  • Killer Frost is an alias used by three different female metahuman super-villains, all of whom were enemies of Firestorm in the main DC Comics continuity. In the pre-Crisis on Infinite Earths timeline, Crystal Frost (introduced in Firestorm: The Nuclear Man #3, in June 1978) was a college student in love with Martin Stein who became the first Killer Frost after a freak accident which imbued her with the power to absorb heat and generate cold. After her death, a new Killer Frost debuted as Dr. Louise Lincoln (in Firestorm #21, in March 1984) a friend of Crystal's who gains the latter's powers through the same means in order to avenge her death. This incarnation of the character made several appearances up until the New 52 relaunch, having been a member of the Injustice League, Secret Society, Suicide Squad and an independent contractor. During the Forever Evil crossover-event of the New 52 relaunch, Caitlin Snow was introduced as the latest incarnation of the Killer Frost persona (as Caitlin Snow in The Fury of Firestorm: The Nuclear Man #19, in June 2013, and as Killer Frost in Justice League of America #7.2, in September of the same year). This character is a S.T.A.R. Labs scientist in the field of thermodynamics, working in the Arctic.
  • The Arrowverse version of Killer Frost, although identified as Caitlin Snow, also shares the Crystal Frost version's affection towards a member of the Firestorm/Deathstorm entity, in this case Ronnie Raymond.
  • When confronting Killer Frost in the forest after finding her, Cisco called her "Elsa", referencing a character from Disney's film Frozen, due to her blonde hair and ice-manipulation powers.


  1. 1.0 1.1 1.2 "Back to Normal"
  2. 2.0 2.1 2.2 2.3 "Welcome to Earth-2"
  3. "Escape from Earth-2"
  4. "Invincible"
  5. "Paradox"
  6. "Monster"
  7. "Killer Frost"
Community content is available under CC-BY-SA unless otherwise noted.