question: What screenwriter was employed by M3 's spouse 's employer , was employed by M1 , and was employed by M2
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.writer .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company ?x1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  ?x1 ns:business.employer.employees/ns:business.employment_tenure.person ?x2 .
  ?x2 ns:people.person.spouse_s/ns:people.marriage.spouse|ns:fictional_universe.fictional_character.married_to/ns:fictional_universe.marriage_of_fictional_characters.spouses M3 .
  FILTER ( ?x2 != M3 )
  }