Nick Jonas and Isabel Lucas have a new co-star in Careful What You Wish For. Dermot Mulroney has joined the Elizabeth Allen-directed thriller, announced Hyde Park-Image Nation and Troika Pictures today. Mulroney will play the investment banker who Lucas’ character Lena is married to while she is having an affair with Jonas’ Doug role. When Mulroney’s character dies and a hefty life insurance policy is reveled, everyone becomes a suspect. Jonas’ addition to the film was announced on March 18. Mulroney recently was set to topline NBC’s drama pilot from writer-executive producer Rand Ravich. The actor will also next be seen in the upcoming jOBS and Osage County with Julia Roberts and Meryl Streep. Mulroney is repped by WME and Barry Tyerman.