For her latest album, Nellie McKay returns to one of her favorite “books,” the Great American Songbook.

And she gives a nod to one of her favorite classic movies.

McKay performs selections from “Sister Orchid,” 8 p.m. Aug. 4, Sellersville Theatre 1894, Sellersville, Bucks County.

After several concerts in New York City, including SummerStage, Central Park, and a four-day series. Sept. 19-22 at Birdland, McKay returns to her home turf of the Poconos, for a concert at the Deer Head Inn, Sept. 29.

The title of McKay’s seventh album is inspired by “Brother Orchid,” a 1940 comedy drama starring Edward G. Robinson, Humphrey Bogart, Ann Sothern and Ralph Bellamy.

“I love that movie. It’s a gangster redemption tale,” McKay says in a phone interview.

In “Brother Orchid,” a mobster (Robinson) hides out in a monastery as a monk.

McKay isn’t inferring that she’s getting to a nunnery. In contrast, she’s been out on tour.

After several concerts in New York City, including SummerStage Central Park, and a four-day series. Sept. 19-22 at Birdland, McKay returns to her home turf, the Poconos, for a concert Sept. 29 at the Deer Head Inn, Delaware Water Gap.

McKay has been lauded for interpretations of the standards.

“Thanks to [McKay], the Great American Songbook has a living, breathing present as well as a glorious past,” raved The Boston Globe.

“A renegade songwriter with an ultraflexible Great American Songbook sensibility, McKay finds modern resonances everywhere,” stated Rolling Stone.

“Sister Orchid” includes McKay’s interpretations of the standards: “My Romance,” “Angel Eyes,” “Small Day Tomorrow,” “Willow Weep For Me,” “The Nearness Of You,” “Georgia,” “Lazybones,” “Where Or When,” “Everything Happens To Me,” and “In A Sentimental Mood.”

“We’ve toured quite a bit already,” McKay says of the album. In July, she performed in Woodstock and Ithaca, N.Y.; Portsmouth, N.H., and Toronto, Canada. Her June concerts included a stop in Eugene, Ore.

Opening the Sellersillve concert is Rich Jenkins. “We are also going to perform some songs together,” McKay says.

’’Sellersville is quite special. It’s a nice hall. It’s the tick capital of the U.S., Pennsylvania, that is,” McKay adds, a trace of wink-wink, nudge, nudge in her voice.

Well, Pennsylvania does translate as Penn’s Woods.

That Shavian wit is effervescent in McKay’s interviews, concert song introductions, and her singing and recordings, like champagne bubbles rising in her sparkling personality and sunny presence.

Nell Marie McKay was born April 13, 1982, in London, England, to Malcolm McKay, an English writer-director, and Robin Pappas, an American actress. She lived with her mother in Harlem, N.Y. and Olympia, Wash., before settling in Mount Pocono, Monroe County.

McKay graduated form Pocono Mountain Senior High School, Class of 2000. She played in the Pocono Youth Orchestra and Phil Woods’ orchestra of young musicians.

Nate Chinen, reviewing McKay’s recording on “Sister Orchid” of “The Nearness of You,” written in 1938 by Hoagy Carmichael with lyrics by Ned Washington, wrote on NPRMusic, “McKay brings an odd bittersweetness, and maybe a whiff of sublimated tragedy, to her delivery.”

McKay accompanies herself on the piano on this song and others on the album, but also on ukulele, harmonica, celeste, harp and cello. The album is released on vinyl and CD.

On her liner notes for “Sister Orchid,” McKay wrote, “This album speaks of the night, the outsider, the plaintive wail of those lost at sea.” Scott Simon, on NPR’s Weekend Edition Saturday, asked her to amplify this and McKay said, “This album is about seeking some kind of solace and not finding it.”

“Sister Orchid” was recorded over the course of a month last year in studios in New York City and the Poconos. Of the Great American Songbook, McKay says by phone, “There’s so many great songs. It’s really hard to choose.

“We have a fair amount of songs that we recorded that we weren’t able to release,” she adds.

In the era when singers weren’t necessarily songwriters, McKay says of the songs, “They’re beautiful. There can be wonderful stuff from any era.

“‘Lazybones’ is a good philosophy of life. People feel that if they don’t do anything, they’re worthless. So much of the problem in the world is ambition.

“Doesn’t everyone identify with that song? I think that song has a sense of humor. I get too lucky to completely identify with that.”

McKay’s career has been anything but luck. In a little more than a decade, she’s been busy.

Her albums include “Get Away From Me” (2004), her debut; “Obligatory Villagers” (2007), which included Poconos jazz greats David Liebman and the late Bob Dorough and Phil Woods; “Normal As Blueberry Pie: A Tribute to Doris Day” (2009), and “My Weekly Reader, Music Of The ‘60s” (2015).

McKay received a Theatre World Award as Polly Peachum in “The Threepenny Opera” in 2006 on Broadway, co-created and starred in “Old Hats” in 2013 off-Broadway, and has written and performed three musical biographies, “I Want to Live!, The Story Of Barbara Graham,” the third woman executed in the gas chamber at San Quentin; “Silent Spring: It’s Not Nice To Fool Mother Nature,” about environmentalist Rachel Carson, and “A Girl Named Bill: The Life And Times Of Billy Tipton,” chosen as one of the best concerts of 2014 by The New York Times, and “The Big Molinsky: Considering Joan Rivers.”

McKay has appeared in the films, “PS I Love You” and “Downtown Express”; the TV shows, “The Late Show With David Letterman,” “Conan,” “Ferguson,” and the radio shows, NPR’s “Mountain Stage,” “A Prairie Home Companion,” “eTown” and “Marion McPartland’s Piano Jazz.”

Her music is on the soundtracks of the movies, “Rumor Has It,” “Monster-in-Law,” “PS I Love You,” “Gasland,” “Last Holiday” and “Private Life,” and the TV shows, “Mad Men,” “Boardwalk Empire,” “Weeds,” “Grey’s Anatomy,” “NCIS” and “Nurse Jackie.”

The Chase Brock Experience produced a ballet of her third album, “Obligatory Villagers.” She contributed the forward to the 20th anniversary edition of “The Sexual Politics Of Meat.” Her writing has also appeared in The Onion, Interview and The New York Times Book Review.

McKay received PETA’s Humanitarian Award and the Humane Society’s Doris Day Music Award in recognition of her dedication to animal rights.

Although in recent years, McKay has often performed acompanied by musicians on guitar, bass and drums, she says she welcomes the opportunity to play solo.

“It’s nice to live simply once in a while,” she says.

McKay is asked about her upcoming projects.

“Let’s see. That I can talk about? No.

“It’s nice to have something simmering,” she adds.

“It’s also nice spend time with your dog. I think that’s the meaning of life.”

Tickets: Sellersville Theater 1894 Box Office, 136 N. Main St., Sellersville; st94.com/event/1687965-nellie-mckay-sellersville/ 215-257-3000