He has claimed in interviews that he didn't really begin to study the piano in earnest until he was in college and studying music. While attending Santa Monica College, he met Sara Lov and started the band Dévics. The quartet released four albums and six singles on Bella Union between 1998 and 2006. O'Halloran began to take the piano seriously while with the band, and then in formal music studies in both Italy and Berlin (where he now resides). He released his first two albums, entitled Piano Solos, Vol. 1 and Piano Solos, Vol. 2 on Bella Union in 2004 and 2006, respectively. During the latter year he was given the opportunity to score filmmaker Sofia Coppola's film Marie Antoinette. In 2009, he composed the score for director William Olsen's An American Affair, which was released on the Filter imprint before the film. In 2010, he scored director Drake Doremus' feature Like Crazy (which won an award at the Sundance Film Festival in 2011). Lumiere, his debut album for Fat Cat's orchestral 130701 imprint was issued in February 2011 to stellar reviews. It featured O'Halloran's piano in a slightly more populated sonic field that included other musicians like the ACME Quartet, Stars of the Lid's Adam Wiltzie, and fellow composer Peter Broderick. This was followed by a live solo piano recording, Vorleben, on the same label in June of that year. ~ Thom Jurek