Harr was discovered in a schoolyard by NRK people who were scouting for actors for youth series.
[citation needed] He soon became a familiar face on programs like Blikkbåx and U and also appeared in the popular 1991 television movie Frida – med hjertet i hånden.
His real film debut came in 2003 in Mot Moskva, where he played the leading role of Vassi and was nominated for an Amanda Award, and in 2005 he appeared in Venner for livet.
He has appeared there as Håkon Håkonsson in Ibsen's The Pretenders and as the young Speer in the production of the same name.
[4] He has appeared in many productions by Jo Strømgren,[4] including There, which won the 2002 Hedda Award for best play.