Superfans arrived dressed as their favourite characters to celebrate the 50th anniversary of popular culture convention Comic-Con.
Fans often spend months preparing for their annual pilgrimage to San Diego, sourcing the parts for costumes which can can cost upwards of thousands of pounds.
The convention floor is filled with people of all ages dressed as their favourite characters, including Batman, Superman and Harry Potter.
Professional cosplay actor Rick Stafford, 49, from Orlando, Florida, said he was inspired to dress as superhero Aquaman in memory of his eight-year-old son, who died of cancer.
He said: “I lost my son to cancer when he was eight years old and he didn’t get to grow up, so I tell people ‘why should I?’.
“I live through my son’s memory by dressing up in cosplay for the rest of my life, so I’m going to be a kid for the rest of my life in his memory.”
Mr Stafford, well known in cosplay circles for his Aquaman suits, said the one he wore on Thursday cost 300 US dollars, about £240.
However, the leather suit he plans to don on Saturday costs 15,000 US dollars, about £12,000.
Michael James Cherry, a 17-year-old student from Redlands, California, came dressed as Pennywise the clown from the It horror movies.
He spent three hours in make-up for the costume, which cost about £150.
He said: “It’s just fun. I love all the people here, I love the comics, pop culture and I love doing different costumes every year. That’s what brings me back.”
Andrew Brady, 21, from Orange County, California, came dressed as an Umbrella soldier from the Resident Evil franchise.
The costume costs an estimated £700 and features genuine military material. Mr Brady is a regular at Comic-Con and said he is attracted by the sense of community.
He said: “I love the community, I love seeing people laugh and smile whenever they recognise costumes.
“It’s nice to be in an environment where you know everyone else is on the same level as you, everyone loves the same nerdy stuff.”
San Diego Comic-Con runs until Sunday.