question: Which actor that M1 influenced and was influenced by was influenced by M2 and influenced by M3 and M4
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.actor .
  ?x0 ns:influence.influence_node.influenced M1 .
  ?x0 ns:influence.influence_node.influenced_by M1 .
  ?x0 ns:influence.influence_node.influenced_by M2 .
  ?x0 ns:influence.influence_node.influenced_by M3 .
  ?x0 ns:influence.influence_node.influenced_by M4
  }