This is a different kind of Martha’s Vineyard ghost story, with a traveling spirit and a supernatural creative partnership.

Few people today recall the composer and music publisher Marshall Rutgers Kernochan, a gregarious summer Islander who helped found the Edgartown Golf Club and was one of the earliest members of the Edgartown Reading Room men’s club.

His Academy Award-winning granddaughter, however, says that some 19 years after Mr. Kernochan died in 1955, his ghost returned to become an abiding presence in both her personal life and her multifaceted career in the arts.

“Thus began a relationship between a family phantom and myself, which has endured, off and on, until the present,” Sarah Kernochan writes in At Home With a Ghost, an online memoir of her life, her work and her sometimes bruising experiences in the entertainment world.

A two-time Oscar winner for documentary filmmaking, Ms. Kernochan also has written and directed feature films, recorded three albums as a singer-songwriter and written two published novels. 

She is currently writing the libretto for a new musical titled Nancy Drew and the Mystery at Spotlight Manor, to be directed by her husband, the Broadway eminence James Lapine.

The couple and their daughter Phoebe Lapine are longtime seasonal residents of Edgartown on waterfront property that once belonged to Ms. Kernochan’s grandfather.

“It’s a lovely bit of beach and an incredible view, and I thank him every day,” she told the Gazette, during a wide-ranging interview last month.

Unlike other generational summer Islanders, Ms. Kernochan didn’t start vacationing here until she was an adult. She hadn’t even seen her grandfather’s house since the summer he died, when she was eight, and assumed in later years that it had been sold.

It was her grandfather who led her back here, Ms. Kernochan told the Gazette, after making his ghostly presence known when she was 27 and staying with her parents at their house in Connecticut in a room filled with old family furniture.

One of the sensations, she said, was of a hand stroking her hair.

“I did not know who it was, but I knew that something was trying to contact me,” Ms. Kernochan said.

A New York city psychic advised her that the spirit was male, known to her and protective, she said.

“And then he said, ‘There’s a house for you in the Cape Cod area, and a ring,’” Ms. Kernochan recalled.

Her father confirmed that the Edgartown house was still in the family, being rented out to vacationers.

“I asked if I could go there to write, because I had my first book contract, and that was the first time I’d seen it since I was a little kid,” she said.

At the house, Ms. Kernochan said, she found her grandfather’s ring and has worn it ever since. As time went by, she also learned to listen for his guidance, although he never physically materialized for her.

“He was seen... by renters when I was managing the house after my folks died, which made me jealous,” Ms. Kernochan said. “I never saw him — I probably don’t have that ability — but I could hear, and he seemed mainly there to give me music, because he was a composer, and he left some stuff unfinished.”

The music would arrive while she was sleeping, Ms. Kernochan said, and linger into her waking moments, enabling her to continue the composition herself.

“He was funneling something to me that I was supposed to write, and I was very resistant and very determined to take the suggestion and then make it my own,” she said.

Ms. Kernochan wound up turning that piece, and others, into Sleeparound Town, a musical revue about puberty that had a 1978 production at the New York Public Theatre — where her future husband, Mr. Lapine, was working on another show.

“That is the piece of music that led me to meet James,” said Ms. Kernochan, who noted that her grandfather’s ghost appeared to approve of Mr. Lapine from the start. With other men, she said, things like ashtrays would sometimes smash for no reason, signaling the late Mr. Kernochan’s disregard.

The same year, Mr. Lapine won his first Obie Award for off-Broadway directing. Ms. Kernochan had previously won an Academy Award and then recorded two albums for a major record label. Her first Oscar came in 1972, for co-directing and co-producing Marjoe, an engaging and startling documentary portrait of a former child preacher who became an evangelical con man. The award looked at first like Ms. Kernochan’s springboard to a film career, but Hollywood presented her with sexist stumbling blocks instead.

“Because I made Marjoe with a partner, it was assumed that I was just a cute little girlfriend,” Ms. Kernochan recalled.

“I wound up with a very powerful agent that I hoped was going to get me some traction, but that turned out to be a kind of Me Too situation,” Ms. Kernochan said, citing the name and slogan of the worldwide campaign against sexual harassment founded in 2006.

“That’s what got me out of the business, which was fine because then I wrote a book, and that’s all I had ever wanted,” she said.

Her debut novel, Dry Hustle, was based on Ms. Kernochan’s adventures with a pair of con women she had befriended in New York City.

“I traveled with them and learned to do what they did, and then based the novel on that,” she said. “It was extremely raunchy.”

The book did well, she said, but everything fell apart with her second novel. Her editor at the publishing house was replaced by someone who cancelled her contract, rendering the book untouchable. 

“It was considered tainted,” she said. “Suddenly, I had no career. It was really weird. That’s why I turned to screenwriting.”

Ms. Kernochan’s first screenwriting credit was for the film 9 1/2 weeks, starring Mickey Rourke and Kim Basinger.

“I have one of those careers that is full of spit takes: ‘She what?’” she said, smiling.

One screenwriting gig begat another, until Ms. Kernochan was able to write and direct a movie of her own: the very funny, but widely overlooked 1998 romp known variously as The Hairy Bird (her original title), All I Wanna Do, AIWD and Strike!

Ms. Kernochan’s second Academy Award, 30 years after the first, came in 2002 with Thoth, her short documentary about a musician and composer who created his own language and mythology. She later commissioned an opera from his duo Tribal Baroque, which was performed at Union Chapel in Oak Bluffs.

Ms. Kernochan finally saw her second novel, the supernatural thriller Jane Was Here, published in 2011, the same year Dry Hustle was released electronically.

Origin of a Kiss, which she’s now rewriting, is more of a literary read, Ms. Kernochan said. It owes its structure and much of its richness to the skills she mastered in the movie trade.

“Screenwriting definitely makes the dialogue come very easily, [and] I became very much more of a daring plotter,” Ms. Kernochan said.

Her grandfather’s ghost is also still very much a part of her life and her work. Her memoir-in-progress, entitled At Home With a Ghost, is posted at sarahkernochan.blogspot.com.