Who directed a film 's prequel and sequel and wrote M1
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:people.person .
?x0 ns:film.director.film ?x1 .
?x0 ns:film.writer.film M1 .
?x1 ns:film.film.prequel ?x2 .
?x1 ns:film.film.sequel ?x2 .
?x2 a ns:film.film
}