What is {performer} of {Dr. John Watson} that is {of} is {Sherlock Holmes} ?
Which actor starred as Dr. John Watson in Sherlock Holmes?
who played Dr. John Watson in Sherlock Holmes?
SELECT ?r WHERE { resource:Dr._John_Watson property:performer ?k . ?k property:performer ?r . ?k property:of resource:Sherlock_Holmes }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q187349> .
?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/Q1764019>
} 

SELECT ?obj WHERE { wd:Q187349 p:P175 ?s . ?s ps:P175 ?obj . ?s pq:P642 wd:Q1764019 }