question: What was a film whose prequel was directed by and starred M1 and M2
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.film .
  ?x0 ns:film.film.prequel ?x1 .
  ?x1 ns:film.film.directed_by M1 .
  ?x1 ns:film.film.directed_by M2 .
  ?x1 ns:film.film.starring/ns:film.performance.actor M1 .
  ?x1 ns:film.film.starring/ns:film.performance.actor M2
  }