Did a producer of M2 's sequel employ a employee of M1 and employ M0 's writer
SELECT count(*) WHERE {
?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x1 .
?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x2 .
?x0 ns:film.producer.film|ns:film.production_company.films ?x3 .
?x1 ns:film.writer.film M0 .
?x2 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
?x3 ns:film.film.prequel M2
}