After years of supporting roles in his native Ireland and the U.K., actor Jason O’Mara became a conspicuous centerpiece for one of the most star-vested network TV projects of recent times. Television hitmaker David E. Kelley attempted for years to transpose the BBC series “Life On Mars” – about a contemporary cop mysteriously transported back to a less lawful 1970s – into one of his edgy comedy-dramas, but was held up by a search for just the right leading man. In 2008, he found that man in O’Mara, casting him alongside such stateside stars as Harvey Keitel, Lisa Bonet, Gretchen Mol and
