He specializes in vocals, guitar and barrels, and is a leading member of the Norwegian band Kaizers Orchestra.

The partnership between Ottesen and Zahl eventually evolved into the band Blod, Snått og Juling.

After gnom's dissolution, the pair finally found critical success in forming the band Kaizers Orchestra.

His 2004 solo album, Francis' Lonely Nights, is entirely in English and contains 12 songs, two of which had their music videos filmed in Scandinavia.

His first single, "Regnbuen Treffer Oss Ikkje Lenger" ("The Rainbow Doesn't Hit Us Anymore"), premiered on Spellemannprisen on 30 January 2016 as he performed it live for the first time.

In 2007, Kaizers decided to take a break for the majority of the year, only writing up demos for their fourth album and playing three concerts (including opening the German art expo Documenta festival).