Brian Dennehy and James Lancaster

Brian Dennehy, right, with son-in-law James Lancaster during a rehearsal for the Mark Taper Forum's production of "The Steward of Christendom." They'll team up for a benefit performance of scenes from other plays for the Los Angeles County High School for the Arts, attended by Dennehy's grandsons. (Bob Chamberlin / Los Angeles Times)

Brian Dennehy will be extending his current L.A. run by one performance -- not in Sebastian Barry’s “The Steward of Christendom” at the Mark Taper Forum, which closes Jan. 5, but in a Jan. 6 benefit for the Los Angeles County High School for the Arts, in which he’ll be surrounded by family.

Dennehy’s two grandsons attend the public arts high school and their parents, veteran stage actors Elizabeth Dennehy and James Lancaster, will support the star in a series of scenes on the school’s stage from plays that Dennehy has starred in or has on his list of coveted roles not yet tackled.

Elizabeth said she and her father are working up a scene from “King Lear” in which she’ll court hisses as one of the turncoat daughters, Goneril, opposite her dad’s tragic king.

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Lancaster, who met his father-in-law before he met his wife, is appearing at the Taper in “The Steward of Christendom” as the chief tormentor of Dennehy's character, a lonely old Irishman who’s been banished by his family to a mental asylum. 

At the benefit they will perform a scene from Ron Hutchinson’s “Rat in the Skull,” the play that first brought them together nearly 30 years ago. They also will perform a scene from Ronald Harwood’s “The Dresser,” with Lancaster playing the titular assistant to Dennehy’s aging lion of the British stage. 

Two members of the arts high school’s drama faculty, Chris Fairbanks and Jeremy Guskin, will join Dennehy for scenes from the star’s two Tony Award-winning roles: as Willy Loman in “Death of a Salesman” and James Tyrone Sr.  in “Long Day’s Journey Into Night.”

Elizabeth said there will be some lighter bits as well, possibly including scenes from “The Odd Couple” or “Twelfth Night” (the benefit falls on the 12th night after Christmas, to which the Shakespeare comedy’s title refers).

She reports that her older son, Jack Lancaster, 16, is a junior at the arts high school focusing on theater -- including a turn as Fleance and Macduff’s son in the Antaeus Company’s 2012 production of “Macbeth” -- and William, 14, is in the school's cinematic arts program. Dennehy also has five granddaughters, the children of Elizabeth’s two sisters.

Tickets are available through the arts high school’s online box office.

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