Switching Roles : Actor Robert Ellenstein will perform in ‘Rocket to the Moon’ under the direction of his son Peter.

Robert Ellenstein worked with Hitchcock and Cary Grant, but they weren’t family.

Son Peter is. Starting this week, the elder Ellenstein, 69, will be directed by his son in Clifford Odets’ “Rocket to the Moon,” a tale about the pursuit of dreams in the modern world. It will run through Aug. 30 at the Company of Characters Theatre in Studio City.

For nine years, Peter, 30, took acting lessons from his father, who says he still has trouble relinquishing his authority.

“I feel somewhat ambivalent,” Robert said. “On the one hand, he should make his mistakes like I did. On the other hand, I’ll pipe up from time to time. I try to restrain myself.”

Peter doesn’t seem to mind. It took him about four years to put the Odets classic onstage and he’s not about to let any struggles for artistic control get in the way.

“I don’t feel any extra pressure with him here,” he said. “A lot of what I do is based on what I learned from him.”

Written in 1938, “Rocket to the Moon” revolves around a Depression-era dentist trapped in a stagnant marriage who begins an affair with his young secretary. The dentist is encouraged by his overbearing father-in-law. Peter always knew who would play the father-in-law.

“The character is imposing, pedantic,” Peter said, “but very funny with a wry, ironic sense of humor. He has a zest for life and a lot of disappointments, too. He reminds me of my dad--larger than life.”

Robert didn’t share his son’s initial enthusiasm about the play. He was concerned that the language and characters might be obsolete. But after rereading it, he changed his mind.

“It’s not a play about changing society,” he said. “It is more about relationships, which is always relevant.”

Peter doesn’t plan to alter much of the language.

“We had a pretty good author. He knew these characters far better than I ever will.”

For Robert, this is the latest role in a busy career. He recently appeared on stage in Portland, Ore., as Tevye in “Fiddler on the Roof” and played a judge in the ABC-TV series “Civil Wars.” In “Star Trek IV: The Voyage Home” (1986), he played the president of the United Federation of Planets.

But perhaps his most famous role was as one of James Mason’s henchmen in Alfred Hitchcock’s “North by Northwest,” a film with one of Hollywood’s most memorable scenes: A crop-dusting plane swoops low in an attempt to kill the character played by Cary Grant. Robert said Hitchcock wanted him to fly in that plane. Hitchcock or no Hitchcock, he refused.

“The plane was going to miss the wires by three feet,” he said. “There was no way I was going to do that.”

Later, he found out the real reason Hitchcock wanted him in that plane.

“They wouldn’t have to pay me anything extra,” he said.

Peter has had small roles in plays and movies but has recently focused on directing. In 1990, he directed and appeared in “Gift Rap” at the Encino Playhouse.

Where and When

What: “Rocket to the Moon.”

Where: Company of Characters Theatre, 12655 Ventura Blvd., Studio City.

Hours: 8 p.m. Thursdays through Saturdays, 2 p.m. on Sundays, through Aug. 30.

Price: $15 on Thursdays and Sundays, $17.50 on Fridays and Saturdays. Call: (213) 466-1767.