Will Ferrell as Lars Erickssong, a middle-aged man with aspirations of winning the Eurovision Song Contest.br br Rachel McAdams as Sigrit Ericksdóttir, Lars' bandmate and long-time best friend, who wishes for a romantic relationship with him.br br Hannes Óli Ágústsson as Olaf Yohansson.br br Olaf Yohansson: Hey, Lars! Get back in there right now and play Ja Ja Ding Dong!br Lars Erickssong: No, we are done for tonight!br Olaf Yohansson: You have to play it!br Lars Erickssong: Why do I have to play it? I already played it.br Olaf Yohansson: I don't care! You have to play it again!br Lars Erickssong: Tell me, when will it be enough for you?br Olaf Yohansson: IT WILL NEVER BE ENOUGH! I ONLY WANT TO HEAR JA JA DING DONG!br Lars Erickssong: Fine, I'll play it! I'll play it. We're having a break.