Double trouble

SELECT * FROM gallery2 WHERE topic_id="20911" UNION SELECT * FROM gallery2 WHERE topic_id="1591539" UNION SELECT * FROM gallery2 WHERE topic_id="1759985" UNION SELECT * FROM gallery2 WHERE topic_id="261510" UNION SELECT * FROM gallery2 WHERE topic_id="715529" UNION SELECT * FROM gallery2 WHERE topic_id="1083302" UNION SELECT * FROM gallery2 WHERE topic_id="643726" UNION SELECT * FROM gallery2 WHERE topic_id="143682" UNION SELECT * FROM gallery2 WHERE topic_id="1258809" UNION SELECT * FROM gallery2 WHERE topic_id="795975" UNION SELECT * FROM gallery2 WHERE topic_id="197053" UNION SELECT * FROM gallery2 WHERE topic_id="562681" UNION SELECT * FROM gallery2 WHERE topic_id="1826474" UNION SELECT * FROM gallery2 WHERE topic_id="1389884" UNION SELECT * FROM gallery2 WHERE topic_id="1666034" UNION SELECT * FROM gallery2 WHERE topic_id="588995"