What is {performer} of {Superman} that is {of} is {Superman} ?
What is the name of the actor who plays Superman in the Superman movie?
Who plays the role of Superman in the movie Superman?
SELECT ?v WHERE { ?y property:performer ?v . resource:Superman property:performer ?y . ?y property:of resource:Superman }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q79015> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P175> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P642> <http://wikidata.dbpedia.org/resource/Q2405659>
} 

SELECT ?obj WHERE { wd:Q79015 p:P175 ?s . ?s ps:P175 ?obj . ?s pq:P642 wd:Q2405659 }