Alien Con 2016
The History Channel hosted a convention for fans of the TV series "Ancient Aliens" and science-fiction enthusiasts in Santa Clara, Calif. over the Halloween weekend. Check out the incredible costumes and celebrity guests in this gallery.
An Alien Con attendee takes a selfie in front of giant sculpture of a wrecked spaceship on Oct. 28.
This Alien Con attendee poses for a photo in the clutches of a vicious-looking alien.
Saber Combat Skills Workshop
Alien Con 2016 hosted a saber combat workshop for attendees on Oct. 29.
An inflatable alien sits behind the reception desk to greet visitors at Alien Con 2016.
An Alien Couple
Two Alien Con attendees dress up for a costume party on Oct. 28.
Alien Faces for Sale
A vendor sells alien masks at Alien Con 2016.
Alien Con 2016 attendees takes pictures of a man in an impressive alien costume on Oct. 29.
UFO Meets Windmill Woman
A UFO appears to be attacking a windmill on a farm in this Alien Con attendee's costume during the costume party on Oct. 28.
Extraterrestrial Photo Op
Alien Con 2016 attendees take souvenir photos at the main exhibition hall on Oct. 28.
Alien Con 2016 attendees dressed in costume at the main exhibition hall on Oct. 28.