Complex sentence: Believing that Charlie needs a vacation, the force tells him to escort a woman named Irene Waters (Renée Zellweger) to Massena, New York because it was reported that she committed a hit and run that was actually committed by Dickie, Irene's partner.
Split into simpler sentences: Believing that Charlie needs a vacation, the force tells him to escort a woman named Irene Waters (Renée Zellweger) to Massena, New York, because she reportedly committed a hit-and-run. However, the hit-and-run was actually committed by Dickie, Irene's partner.