What film whose writer was employed by M2 and M3 was written by M1
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:film.film .
?x0 ns:film.film.written_by ?x1 .
?x0 ns:film.film.written_by M1 .
?x1 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
?x1 ns:people.person.employment_history/ns:business.employment_tenure.company M3
}