Complex sentence: He co-wrote "Heathers", a musical based on the movie of the same name, written by O'Keefe, Andy Fickman and Kevin Murphy, which premiered in Los Angeles in 2013 and off-Broadway in 2014.
Split into simpler sentences: He co-wrote "Heathers", a musical of the movie of the same name. It premiered in Los Angeles in 2013 and off-Broadway in 2014.