By John Young
Updated February 11, 2010 at 10:50 PM EST

John C. Reilly has joined the cast of We Need to Talk About Kevin, according to Variety. Reilly will play the dad of a 15-year-old boy who goes on a killing rampage. Tilda Swinton has been cast as the boy’s mother. British filmmaker Lynne Ramsay (Morvern Callar) will direct and write, and Steven Soderbergh will serve as the film’s executive producer.