Did M3 employ a screenwriter that influenced M1 and M2 and employ M4
SELECT count(*) WHERE {
?x0 a ns:film.writer .
?x0 ns:influence.influence_node.influenced M1 .
?x0 ns:influence.influence_node.influenced M2 .
M3 ns:business.employer.employees/ns:business.employment_tenure.person ?x0 .
M3 ns:business.employer.employees/ns:business.employment_tenure.person M4
}