Hillsong—which originated in Australia in 1983 before expanding globally over the next several years, including at one point 16 locations in the U.S.—isn’t your typical megachurch. At its height in popularity throughout the 2010s, you had to fight to get a seat inside. “I remember going down on a Sunday morning to Hillsong Church LA and there were literally people wrapped around the block to get in,” David Collins, the executive producer of the new documentary series The Secrets of Hillsong, tells TIME.