Actor Matt Damon, who stars as the amnesiac former assassin Jason Bourne in the new film,
'The Bourne Ultimatum,' poses Saturday, July 21, 2007, in Los Angeles.[AP]

Frank Marshall won't rule out another sequel to the Jason Bourne films, but says the story has already ventured far afield from Robert Ludlum's novels.

"There might be an idea out there that we could go forward with, but right now, the trilogy is done," Marshall said Monday at a screening of "The Bourne Ultimatum."

Matt Damon, who stars as amnesiac assassin Jason Bourne, also attended the screening, a fundraiser for the Boise Contemporary Theater. The event was held at the Egyptian Theatre.

Marshall and Damon have attended screening events in Boise for each Bourne movie. Marshall has local ties to Boise, and has held several premieres in the city to benefit various causes.

Damon said he hoped future projects bring him back to Idaho.

"I'm hoping that a lot of people from the industry come to Idaho — the mountains, the desert, the city, with everything that you have going for you, more movies should be shot out here," the 36-year-old actor said.

"The Bourne Ultimatum" opens in theaters nationwide Friday.