At Sierra's preview event, I got a chance to take a look at an early build of the upcoming Ghostbusters game, in development by Terminal Reality and slated for a Fall release on PlayStation 3, Xbox 360, Wii, PS2, DS and PC. One of the big things I learned was how involved Dan Aykroyd, who played Peter Venkman in the films, was in the game production.

Apparently it was Aykroyd who got all of the other cast members on board to do the voice-overs, and he was so enthusiastic about the game that he helped name and create specs for many of the game's weapons, to make sure they sounded and played like something that would have really been part of the franchise. In fact, Aykroyd is co-writing the entire script with fellow Ghostbusters writer Harold Ramis, so it's a game adaptation with what look to be strong ties to the original material.

The city of New York plays a major role here, too, and from what I saw and was told, the developers are aiming for a true-to-life NYC that echoes the environment in the films, from indoors to out - the city as a "character," as the reps said.

They told me they're aiming for a "seamless" transition between the game's indoor and outdoor environments. I also learned why you won't get to play as any of the four Ghostbusters.

In the game, you play a new recruit to the team whose primary role is to act as "guinea pig" for all of Egon's new weapons. You play as part of a team with the other Ghostbusters, and the reps told me they really want to capture the "comedic timing" of the interaction among the characters - with the player controlling one, it might interfere, as you can probably imagine.

Ghostbusters: The Video Game is set in 1991, three years after the second film. The mayor has just been re-elected on a pro-Ghostbusters platform, and he's now funding the team's latest activities. However, it looks like the team will end up racking up more in city damages during the poltergeist fights than it earns in fees for eliminating the beasties.

In the scene I saw, the player and two teammates fought a ghost inside New York Public Library. That scene alone, the reps told me, had about 4,000 destructible objects inside it, and as items were destroyed, they got sucked into the ghost's body. Characters can be created out of physics objects in realtime, the reps explained.

And for every shelf, chair, book and lamp the team bashed up, a little running cash tally in the corner of the screen showed how much dollar damage the player had racked up. There's no penalty for this, the reps explained - it's intended as a fun sort of points system.

New weapons become available from Egon and they can be upgraded and customized using your earnings from successful ghost hunts. The way the weapons system works, you can see what's going on on the back of your equipment pack - for example, instead of an ammo system, you watch your heat cylinders and have to take a pause when you overheat. Keep an eye on it, though, and you can vent it manually.

In another scene, I watched the team battle the iconic Stay Puft Marshmallow Man from inside a city building, escaping out onto the roof to trap little bits of him that had separated off and begun attacking. When you use your beam to lasso a ghost, the reps said, the teammate AI knows what you're up to and will provide a trap for you.

I also learned a little bit about how the multiplayer will work on Xbox Live and PlayStation Network - it's cooperative for up to four players who compete against each other for the leaderboards.

The team also said the PlayStation 3 was the game's "anchor platform," and built in Sixaxis controls for the beam weapons on that version. For the less-powered system, developer Red Fly is preparing a more stylized, cartoon version that's more mission-based for Wii and PS2, while the DS version is more focused on being a "throwback to the 90s." (We also hear the DS can connect up to the Wii and act as a PKE meter). Each version, I was told, is totally different, but they're all "by fans, for fans," as the reps said.