Last night, Canadian pop duo Tegan and Sara took the stage on 'Conan' -- backed by the Los Angeles Grand Arts High School Choir -- to perform their heartfelt track, ‘I Was a Fool,’ from their latest album, ‘Heartthrob.’ Check out the beautiful vocalization and piano accompaniment in the video above.

‘Heartthrob’ is the twins’ seventh studio album, released in 2013 via Vapor/Warner Bros. Records. It’s the girls’ most commercial pop-sounding record, which is atypical since they have strong ties and influences from the punk rock and alternatives scenes.

Despite the new record’s different direction, Tegan and Sara have always had a pension for live sound. They’ve collaborated with everyone under the sun, including popular punk rock luminaries Alkaline Trio. To get a feel for the other end of their spectrum, watch Tegan and Sara perform ‘Wake Up Exhausted’ with Alkaline Trio below: