Costumed fans dressed as superheroes and villains are descending on San Diego for the 45th annual Comic-Con.

More than 150,000 fans are expected to attend the four-day festival celebrating film, TV, video games, comic books and costumes.

After more than four decades of Comic-Con, the festival has outgrown the San Diego Convention Centre and spills out on to neighbouring streets and hotels.

Wonder Women, Batmen, Klingons and the undead mill about the streets of the city. IBTimesUK takes a look at some of the attendees at this year's event.

Allie Shaughnessy, dressed as Marvel Comics' character Mystique, attends Comic-Con 2014 in San Diego, California
Allie Shaughnessy, dressed as Marvel Comics' character Mystique, attends Comic-Con 2014 in San Diego, CaliforniaReuters
Maia Blackman, dressed as Lorne from the TV series Angel, attends Comic-Con
Maia Blackman, dressed as Lorne from the TV series Angel, attends Comic-ConReuters
Costume designer and viral marketer Chad Evett and members of his family, dressed as the Mad Hatter and the Red Queen, pose outside the San Diego Convention Centre
Costume designer and viral marketer Chad Evett and members of his family, dressed as the Mad Hatter and the Red Queen, pose outside the San Diego Convention CentreAFP
Nomad, lead singer of the band Dive Bomber, strokes a puppy held by seven-year-old Ashton Ritz, dressed as Jack-Jack from The Incredibles
Nomad, lead singer of the band Dive Bomber, strokes a puppy held by seven-year-old Ashton Ritz, dressed as Jack-Jack from The IncrediblesAFP
A dog named Ollie is dressed as Captain Marvel
A dog named Ollie is dressed as Captain MarvelReuters
Two Doctor Who fans dress as the fifth incarnation of the Doctor, played by Peter Davison
Two Doctor Who fans dress as the fifth incarnation of the Doctor, played by Peter DavisonGetty
Doctor Who fan Allie Marie, looks out from her homemade, life-sized, Tardis
Doctor Who fan Allie Marie, looks out from her homemade, life-sized, TardisGetty
Christopher Petrone of San Diego towers over attendees in his handmade Chewbacca costume
Christopher Petrone of San Diego towers over attendees in his handmade Chewbacca costumeGetty
William Pasini of Santa Barbara poses as Worf, a Klingon in Star Trek
William Pasini of Santa Barbara poses as Worf, a Klingon in Star TrekGetty
Erien Hodge and his son Adonis, 13, dress as Batman and Robin
Erien Hodge and his son Adonis, 13, dress as Batman and RobinAFP
Attendees dress up as Disney villains Hades, Maleficent and Yzma
Attendees dress up as Disney villains Hades, Maleficent and YzmaAFP
Sirisha Verigonda poses as Michonne from The Walking Dead with two zombies, Emily Zheng and Gina Huang
Sirisha Verigonda poses as Michonne from The Walking Dead with two zombies, Emily Zheng and Gina HuangGetty
Kenneth McDaniel, dressed as Homer Simpson, arrives at Comic-Con
Kenneth McDaniel, dressed as Homer Simpson, arrives at Comic-ConReuters
Karl Zingheim arrives at Comic=Con in his Game Of Thrones White Walker costume, complete with undead horse
Karl Zingheim arrives at Comic=Con in his Game Of Thrones White Walker costume, complete with undead horseGetty