Question: What movies starring Zac Efron were released before 2015?
Answer(s):
answer: Parkland
answer: The Lorax
answer: 17 Again
answer: High School Musical
answer: At Any Price
answer: Melinda's World
answer: Me and Orson Welles
answer: If You Lived Here, You'd Be Home Now
answer: High School Musical 2
answer: High School Musical 3: Senior Year
answer: New Year's Eve
answer: Autobahn
answer: The Lucky One
answer: That Awkward Moment
answer: Neighbors
answer: The Paperboy
answer: Charlie St. Cloud
answer: Robot Chicken: Star Wars Episode III
answer: Miracle Run
answer: The Derby Stallion
answer: Hairspray
answer: Liberal Arts
answer: The Big Wide World of Carl Laemke

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.06wm0z)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.06wm0z ns:film.actor.film ?y .
?y ns:film.performance.film ?x .
?x ns:film.film.initial_release_date ?num .
FILTER (?num < "2015"^^xsd:dateTime) . 
}