Tracy Ullman talks ‘The Serial Killer’s Apprentice’

True crime writer and producer Tracy Ullman joins Karen Conti to discuss the newly released HBO documentary ‘The Serial Killer’s Apprentice’, which is based on a book by the same name that was co-authored by Tracy. Tracy talks about serial killer Dean Corll and accomplice Elmer Wayne Henley Jr., who assisted in the murders of at least 27 young men and boys in Texas in the 1970s.