He left England for New York, where he would meet his wife, Miranda Cowley, granddaughter of the American poet and critic Malcolm Cowley. After five years in the city, Heller moved to Los Angeles, where he worked on various television dramas including two projects for the USA Network: Touching Evil and The Huntress. But his breakthrough came with Rome, which he co-created. After the cancellation of that series for its high costs, Heller created The Mentalist. In September 2012, Heller sold a legal drama named The Advocates to CBS, which was written and executive produced by him, but the project finally did not go to series. In 2014 Heller created a TV series based on the Batman character James Gordon called Gotham for Fox Broadcasting Company.