Was M2 a sequel of a film whose editor and star edited M1
SELECT count(*) WHERE {
?x0 a ns:film.film .
?x0 ns:film.film.edited_by ?x1 .
?x0 ns:film.film.starring/ns:film.performance.actor ?x1 .
?x1 ns:film.editor.film M1 .
M2 ns:film.film.prequel ?x0
}