Having coffee with Batman and Superman at Comic-Con

Every year the San Diego Convention Centre is filled to bursting point with fans and followers of everything associated with science fiction, superheroes, cult movies and comic books.

Comic-Con attracts fans of all ages.

Sunshine drenches the city of San Diego as it bathes in the glow of another glorious summer's day. The streets of the old Gaslamp Quarter are packed with people. Comic-Con has arrived and the carnival is in full swing. Every year the Convention Center is filled to bursting point with fans and followers of everything associated with science fiction, superheroes, cult movies and comic books.

Not only is it a gathering of all things geek; Comic-Con has become by far the biggest single cinematic event in terms of news and announcements. Yes, it focuses on sci-fi, cult movie and comic genres that you might think don't relate to you, but whether you realise it or not, you do dip into the genre. Batman, Spider-Man, The X-Men, Superman, The Watchmen, Iron Man and Star Trek all fall into this category. Only the Academy Awards puts more movie stars in one place.

This is an environment where you can be, and probably will be, judged on your worth simply according to the T-shirt you're wearing. A bog-standard Batman logo T-shirt, for instance, is little more than a token attempt and you would be considered an amateur. However, if you have one with the Kirby Silver Surfer on it, or a Silver Age Flash T-shirt, then you earn some serious geek kudos. This is all of course providing you haven't gone in costume. That truly separates the men from the boys - and girls. Comic-Con isn't just for guys: half of the colossal crowd in attendance is female.

The Mardi Gras mood that grips the city is enhanced by the sheer number of fans around the show floor and walking the streets dressed in costume. The roads are closed off to traffic, every eatery with outdoor seating is full and live bands play on the occasional street corner. When I'm there, Pacman and a medley of ghosts meander past, and the Ectomobile from Ghostbusters is parked on one side and drawing a big crowd.

Comic-Con gets bigger every year and there were some enormous events in 2010, the biggest draw probably being the new Tron movie. This is the much-anticipated sequel to the 1982 original that promises more spectacular special effects than Avatar - and certainly more of a story. As it happens, the mind-blowing CGI is integral to the plot as the story takes place inside a computer mainframe - on the other side of the screen.

The press conference for Tron: Legacy, as it's called, was the first big event of my visit, and thousands of fans were crowded outside one of the halls, queuing for the Tron panel (where members of the cast and often the writers and directors take questions, tell anecdotes and give the fans a chance to voice their views) for which some had camped out overnight. They, and the very special press who were attending as guests of Disney (the studio distributing the new movie), were rewarded with a line-up the stars, Jeff Bridges, Bruce Boxleitner, Michael Sheen and Olivia Wilde, and the writer and director, as well as a premiere of the brand new trailer for the movie.

Meanwhile, the Battlestar Galactica panel was being held and I managed to secure a respectable spot in a filled-to-capacity room. I watched in awe as a hero from my childhood, Richard Hatch - who played Captain Apollo in the original series and the charismatic Tom Zarek in the recent reimagined version - took to the stage and performed, in essence, 15 minutes of stand-up comedy to the captivated crowd. After which other members of the cast and crew joined him and took questions from the gathered fans. They laughed, they joked, they entertained and they were clearly enjoying themselves.

It turns out the actors, writers, directors and producers enjoy being with the fans: it's fun for them and they clearly relax. Comic-Con is also about cast and crew reuniting after working closely together for many years. Quite often they haven't seen each other for some time, and a fans get to share in their reunion. Over in the autograph hall countless little booths contain film and TV stars from the world of cult film, each with queues varying in length depending on who was signing pictures. No where else in the world would you see Dirk Benedict in a booth next to Val Kilmer in a booth next to Patrick Duffy who's next to Rick from Magnum PI.