LOS ANGELES -- The next "Indiana Jones" flick will not be another father-son affair. Sean Connery says he will not return to play dad to Harrison Ford's globe-trotting adventurer Indy.

Connery played Indy's father in 1989's "Indiana Jones and the Last Crusade," the third installment of the franchise directed by Steven Spielberg and produced by George Lucas.

"I get asked the question so often, I thought it best to make an announcement," Connery, 76, said in a statement posted Thursday on Lucasfilm's "Indiana Jones" Web site. "I thought long and hard about it, and if anything could have pulled me out of retirement it would have been an Indiana Jones film."

"I love working with Steven and George, and it goes without saying that it is an honor to have Harrison as my son," he said. "But in the end, retirement is just too damned much fun."

The fourth film, not yet titled, is again directed by Spielberg and produced by Lucas. Shooting begins the week of June 18 at an undisclosed U.S. location, and the movie is due out May 22, 2008.

Lucasfilm also announced Thursday that Cate Blanchett, John Hurt and Ray Winstone will be joining the cast, which along with Ford, includes Shia LaBeouf.

Lucas and Spielberg have been working with a variety of screenwriters over the years on the long-awaited sequel. The filmmakers have kept the story under wraps, with Lucas, Spielberg and Ford saying in interviews only that it would take place sometime after World War II. The first three movies were set in the mid- to late 1930s.

Lucas and Spielberg are maintaining tight secrecy because details on story and casting are still being worked out and because they want to save some surprises for audiences, said Spielberg spokesman Marvin Levy.

"This is the closest to the vest I've seen. Does Indy wear a vest?" Levy said. "We have more speculation about a number of people than anything I have ever encountered."