LOS ANGELES (Reuters) - They may be father and son and Hollywood royalty to boot but they trade quips like a pair of Borscht Belt comedians and memories like best friends.

Because he is older -- 86 -- and his knees are hurting, Kirk Douglas gets to lie on the hotel bed while his son Michael, 58, gets the uncomfortable bedroom chair as the two give an interview on the first film they have appeared in together, a three-generational drama opening on Friday called "It Runs in the Family."

"See what happens when you do your own stunts," Michael tells his father in a mock effort to comfort him.

"The doctor who was examining me said, 'Do you do your own stunts?' and I said, 'Yes,' and he said, 'I can see that,"' Kirk replies. "It could be worse."

"Yes," Michael says, "It could have been worse" and then laughs a bit nervously, perhaps thinking of the stroke his father suffered in 1996 that left him with slurred speech and a depression so deep that he once stuck a gun in his mouth before deciding against suicide.

But Kirk, who spent years overcoming his stroke to successfully return to acting, interjects with a different story. He recalls a 1991 helicopter crash he was in that resulted in the deaths of two young men, including one 18-year-old who was preparing for his senior prom.

"And that's what started you on your spiritual quest?" Michael asks his dad who replies, "What's that?"

"Don't you speak English," Michael responds, not missing a beat.

A PAIN IN THE...

At that point, the pair is asked what it was like to work together and Michael is at no loss for words, "He's a pain in the ass and I know his line; he will say he is difficult."

To which Kirk answers with a story, "Burt Lancaster once introduced me by saying, 'Kirk Douglas is the first to admit he is difficult to work with and I will be the second."'

He adds, "Michael (who produced the movie) is a tough guy to work for. He doesn't pay much. You have to love the script..."

Michael turns serious about "It Runs in The Family," a drama about members of a prominent New York family who seem successful on the surface but are coming apart at the seams. At the heart of the story is an estrangement between father and son that transforms into an unexpected bonding.

"The biggest joy was watching the amount of homework that dad did on this, his 86th movie -- the amount of analyzing and looking at scenes, coming up with new ideas that are insightful and stimulating," he says.

"I learned a lot from dad. He always said a good actor knows how to listen. One of the joys of acting with dad is the effortless quality of being there that he brings. He makes things so believable."

Kirk is moved: "That's nice for an actor who won two Academy Awards to say. I didn't realize I was so good."

"You're wonderful," the son says.

Kirk returns the compliment: "I thought Michael was a good actor, the first scene I played with him. He was better than I thought he was and I thought he was very good. You know he played Gordon Gekko in 'Wall Street' (a film for which he won an Oscar for best actor) and was so convincing that he made people believe greed was good.

A FAMILY AFFAIR

Besides Kirk and Michael, the film stars Kirk's ex-wife, Diana Douglas, who is also Michael's mother, Michael's son Cameron and a young actor named Rory Culkin, who hails from an unrelated show business family.

The credits also list Joel Douglas, Michael's brother, as associate producer and the family photos on display in several key scenes are straight out of the Douglas family album.

Michael says, "The big joy and surprise was Cameron. Initially we were concerned and nervous about whether he could act but once we saw what Cameron could do, we had a ball. We could relax and be happy."

In fact, Cameron comes close to stealing the movie -- hamming it up with three of the best, his father, grandfather and grandmother. Acting runs in the Douglas family and also includes Michael's wife, Cameron's step-mother and Kirk and Diana's daughter-in-law -- Oscar winner Catherine Zeta-Jones.

"It was a unique experience. The first time out that three generations have been in one picture. It brought us closer together, sharing an experience. If you can survive making a movie, you can survive anything," says Kirk, whose films include "Spartacus," "Champion" and "Lust for Life."

"Dad is such a good actor that when my brother and I saw him in 'Lust for Life," I completely forgot it was him," Michael says.

For years Michael and Kirk had been looking for a project, with Kirk still smarting at giving his son the rights to produce "One Flew Over the Cuckoo's Nest" with another actor, Jack Nicholson. Michael won an Oscar for making the film.

Then after they found this project, Kirk had a stroke. "I thought I would never be able to make a picture again. This is like having a career all over again.