What person that M1 was influenced by and M2 was influenced by did M3 and M4 star
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:people.person .
?x0 ns:film.actor.film/ns:film.performance.film M3 .
?x0 ns:film.actor.film/ns:film.performance.film M4 .
?x0 ns:influence.influence_node.influenced M1 .
?x0 ns:influence.influence_node.influenced M2
}