question: Did a star of a sequel of M1 produce a film
query: SELECT count(*) WHERE {
  ?x0 ns:film.actor.film/ns:film.performance.film ?x1 .
  ?x0 ns:film.producer.film|ns:film.production_company.films ?x2 .
  ?x1 ns:film.film.prequel M1 .
  ?x2 a ns:film.film
  }