The new film is a remake of the 1981 version which starred Laurence Olivier.
A film buff got to go behind the scenes of Clash of the Titans during location shooting in Snowdonia and Anglesey, then mingled with the stars at the premiere in London this week.
Alan Hughes from Anglesey explained how he was granted special access.
"I run a couple of websites on films which were shot in north Wales - Half Light with Demi Moore and Tomb Raider II. So when I heard Clash of the Titans was coming I managed to get in touch with the director, Louis Leterrier," he said.
"I wasn't expecting a reply, but he invited me up to the set in Dinorwig Quarry."
Alan was able to watch Dinorwig being transformed into a battleground between Perseus (played by Sam Worthington), the son of a Greek god, and Hades, vengeful god of the underworld.
"One of the biggest changes they'd made was to pump dry one of the quarry's ponds," Alan said. "They needed to film at the bottom of it, but it must have taken a lot of work."
Location shooting brought a boost to the local economy
Though Alan, who works in Manchester, wasn't allowed to stay and watch the action, he did see the making of one of the monsters.
"It's hard to explain exactly what it was," said Alan. "It was like these really big scorpions which the characters are travelling on top of. They were quite impressive, but very strange.
"They'd also brought in lots of camels, which was a bit of a random thing to see!"
As the second largest such quarry in the world, Dinorwig gives filmmakers the space to get creative, says Alan who has created his own Clash of the Titans website.
"I've already had emails from all over the world from people saying how amazed they are by the quarry," he said. "It's just unique. People are really interested in finding out about film locations like this."
Alan discovered that the crew had taken to the air above Snowdonia to get sweeping shots of the quarry from above. They also filmed in Newborough woods and Malltraeth beach on Anglesey.
Actress Gemma Arterton, who plays Io, told Alan at the premiere on Monday she thought Anglesey was absolutely beautiful.
But Nicholas Hoult (Eusebios) wasn't too fond of the Snowdonia weather.
"He said it was really difficult because it was raining every day, but that filming there really pays off when you watch it back on film," said Alan.
A veteran of several film premieres, Alan puts this one at the top of his list, despite the fact that he didn't have a ticket and will have to see the film when it goes on general release on Friday, 2 April.
"It was really exciting. They'd designed new set pieces from the film and had people dressed as Titan soldiers walking around," he said.
"The director thanked me for doing the site. He hopes people will want to visit the locations after seeing the film. They said the locations looked spectacular.
"I've seen an aerial shot of the quarry and, even though they've used a bit of CGI [computer-generated imagery], overall the scenery hasn't been changed. I'm really looking forward to seeing the finished film."