question: Who was a actor that M4 's sequel was executive produced by , M2 was directed by , and M3 was directed by
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.actor .
  ?x0 a ns:people.person .
  ?x0 ns:film.director.film M2 .
  ?x0 ns:film.director.film M3 .
  ?x0 ns:film.producer.films_executive_produced ?x1 .
  ?x1 ns:film.film.prequel M4
  }