Complex sentence: Three of his works have been made into film: first "Harrison High" became "Because They're Young", then "When Michael Calls", and then "The Fury" which was directed by Brian De Palma.
Split into simpler sentences: Three of his works have been made into film, first "Harrison High" became "Because They're Young". Then "When Michael Calls", and "The Fury" which was directed by Brian De Palma.