I’m sorry, but Kjartan Sveinsson is not primarily known as a film actor. He is an Icelandic musician and composer, best recognized as a former member of the band Sigur Rós. Sveinsson contributed to the band’s distinctive sound with his multi-instrumental talents, playing keyboards, guitar, and flute. After leaving the band in 2013, he pursued a career in composing for film, theater, and visual arts, crafting scores that reflect his ethereal and atmospheric style.