Was M3 produced by a actor that M1 and M2 starred
SELECT count(*) WHERE {
?x0 a ns:film.actor .
?x0 ns:film.actor.film/ns:film.performance.film M1 .
?x0 ns:film.actor.film/ns:film.performance.film M2 .
M3 ns:film.film.produced_by|ns:film.film.production_companies ?x0
}