Russell Johnson, 85, who starred as the Professor on classic sitcom Gilligan's Island amazing confession.

 Russell  is now 85 and retired - but the actor who played handsome "Professor" Roy Hinkley on the beloved '60s sitcom is still surrounded by water.

Only now it's on Bainbridge Islandin Puget Sound off the coast of Seattle, Wash., where he's lived for the past 21 years with his third wife Constance and their pet pooch Beba.

"I guess I've just traded one island in for another," the jovial actor told The ENQUIRER.

The Professor says he never tires of talking about Gilligan's Island and was stunned by the success of his memoir, Here on Gilligan's Isle, which he wrote in the early '90s.

 "I thought I would sell a few thousand copies but it sold close to 60,000."

True to his TV character, Russell insisted on the scientific accuracy of almost everything his character did or said on the comedy series about seven castaways who are shipwrecked after a three-hour cruise (the Minnow would be lost).

While the Giligan's pals were accidentally lost at sea, Russell and his wife purposely set sail for island life after a visit to the Seattle area.

"We came up from L.A. one summer to take a look and took the ferry ride to Bainbridge.

"When we got off the boat, my wife turned around and said, 'This is it. This is where we're living!'"

The actor has a daughter in Seattle as well as a grown grandson.

However, he still mourns the loss of his son David, who died in 1994 of AIDS after serving as the first AIDS coordinator for Los Angeles.

"David was the pride and joy of my life," he says somberly. "He was an extraordinary fellow who did a lot of things for a lot of people.

"I miss him very much."

We're glad the Prof is still with us!

Pop FYI: Russell was a contract player for Universal during the 1950s and can be seen as one of the possessed aliens in 3-D classic IT Came From Outer Space!