06/01/2013 11:28 am ET Updated Aug 01, 2013

Denver Comic Con: 2nd Annual Convention A Hit With William Shatner As Guest Of Honor

The Denver Comic Con has returned, and it's such a hit this year that approximately 6,000 fans waiting in line for tickets at the Convention Center had to be turned away by the fire marshal and Comic Con staff.

"Some people were livid," Ami Heinrich, spokeswoman for Denver Comic Con, told The Denver Post. "Everyone who already had a ticket got in."

The website for this year's Comic Con even crashed Wednesday due to exorbitant amounts of traffic, according to officials.

Ticket sales are up 47 percent for Denver's second annual Comic Con -- here through Sunday -- and the guest of honor is William Shatner. George Takei, who played Sulu in the original "Star Trek" franchise, Wil Wheaton, Erin Gray and other celebrities are also expected to be in attendance at the comic convention.

Comic legend Stan Lee was originally slated to be the guest of honor and make a rare appearance at the convention but had to cancel due to a film shoot. Lee is credited with co-creating such comic book characters as Spider-Man, the Hulk, X-Men, the Fantastic Four, Iron Man and Thor.

The program art for this year's Comic Con (which can be seen in the link above) was drawn by native Aurora artist J. Scott Campbell.

“Cons are a big part of my income," Campbell told 5280. "Ten years ago, we’d do it just to do it. Now, we do it because it’s important. If fans can meet us and also have an experience, that’s even better.”

Registration for this year's costume contest is closed, though fans can still cheer on the contestants. It will be held Saturday, June 1, from 6 to 9 p.m. at the Four Seasons Ballroom in the Colorado Convention Center downtown.