After Frank The Fixer Tagliano testifies against his Mafia boss in New York, he enters the Witness Protection Program and makes an unusual demand: he wants to be set up with a new life in the Norwegian small town of Lillehammer or as he calls it, Lilyhammer.

When timid bank clerk Stanley Ipkiss discovers a magical mask containing the spirit of the Norse god Loki, his entire life changes. While wearing the mask, Ipkiss becomes a supernatural playboy exuding charm and confidence which allows him to catch the eye of local nightclub singer Tina Carlyle. Unfortunately, under the mask's influence, Ipkiss also robs a bank, which angers junior crime lord Dorian Tyrell, whose goons get blamed for the heist.