When Elsa is looking for Anna, she goes to the stables where Kristoff is with his reindeer Sven. The two talk about Anna's whereabouts, where Elsa realizes that Kristoff is trying to stall her. He eventually tells her that she has caught a ship that is sailing to a place called Misthaven, which is where Anna and Elsa's parents were voyaging to when they died in a storm. After Kristoff finds out that Hans has plans to trap Elsa with an ancient urn, he and Elsa go out to locate the urn before Hans can. However, Elsa eventually surrenders the urn to Hans, when he threatens Kristoff's life. Hans opens the urn, but instead of trapping Elsa, it releases Ingrid, who magically freezes Hans with magic similar to Elsa's. Kristoff and Anna are reunited when Anna returns from her journey, although Ingrid freezes them both.
Thirty years later, the magic wears off on Kristoff and Anna, but also releases Hans, who captures the two of them and has them locked in a chest on Blackbeard's ship, which is then tipped overboard in an attempt to have them killed. However, when Elsa wishes that Anna would be there, having only her sister's necklace to remember her by, it is revealed that the necklace is a magical object called the Wishing Star. Kristoff and Anna are teleported to Storybrooke where Elsa currently is, and they all reunite, although Ingrid is also there, and casts the Spell of Shattered Sight over all of Storybrooke. When the Spell is broken, Kristoff returns to Arendelle with Anna and Elsa, and they take Arendelle from Hans. Afterwards, Kristoff and Anna finally get married.
- He is based on Kristoff from the Disney film Frozen, an adaptation of the fairytale The Snow Queen.
- Kristoff owns a reindeer named Sven.
- S4, E01: "A Tale of Two Sisters" (flashback)
- S4, E03: "Rocky Road" (flashback)
- S4, E04: "The Apprentice" (flashback)
- S4, E06: "Family Business" (flashback)
- S4, E08: "Smash the Mirror" (flashback)
- S4, E09: "Fall"
- S4, E10: "Shattered Sight"
- S4, E11: "Heroes and Villains"