Looks like I got myself into quite the situation...

SELECT * FROM gallery2 WHERE topic_id="1504369" UNION SELECT * FROM gallery2 WHERE topic_id="1326322" UNION SELECT * FROM gallery2 WHERE topic_id="353287" UNION SELECT * FROM gallery2 WHERE topic_id="1724738" UNION SELECT * FROM gallery2 WHERE topic_id="556749" UNION SELECT * FROM gallery2 WHERE topic_id="312453" UNION SELECT * FROM gallery2 WHERE topic_id="812964" UNION SELECT * FROM gallery2 WHERE topic_id="1441055" UNION SELECT * FROM gallery2 WHERE topic_id="1802554" UNION SELECT * FROM gallery2 WHERE topic_id="234776" UNION SELECT * FROM gallery2 WHERE topic_id="54238" UNION SELECT * FROM gallery2 WHERE topic_id="1238441" UNION SELECT * FROM gallery2 WHERE topic_id="614644" UNION SELECT * FROM gallery2 WHERE topic_id="1798024" UNION SELECT * FROM gallery2 WHERE topic_id="32090" UNION SELECT * FROM gallery2 WHERE topic_id="1550599"