The pilot episode's world premiere was on July 24, 2004 at San Diego Comic-Con.[24] Part 1 had its first ABC broadcast on September 22, 2004, reaching a ratings record for a pilot episode, with 18.6 million viewers,[25] and on the following week, part 2 scored 10.5/17 on the Nielsen ratings, watched by 17 million viewers.[26] Both parts aired on the same night for its first UK broadcast on Channel 4, August 10, 2005, and it became an instant hit.