In "Wild Nights With Emily," Shannon gives gay Emily Dickinson her unique spark, adding great depth befitting the misunderstood poet.

In the storied history of “Saturday Night Live,” Molly Shannon is one of the few performers whose characters are as famous as they are. You can trace a pretty straight line from Gilda Radner’s Roseanne Roseannadanna to Molly Shannon’s Mary Katherine Gallagher, and her intensely wacky characters paved the way for Kristen Wiig and Kate McKinnon.

While many former cast members go on to blockbuster comedy success, fewer have sought out — and secured — serious acting careers. “Barry” has made Bill Hader a peak-TV darling, nobody saw Will Forte’s “Nebraska” performance coming, and Wiig has worked with an enviable roster of directors. It’s far more common to go the way of Tina Fey, Amy Poehler, or Will Ferrell, who built empires on broad studio comedies.

Shannon, by contrast, didn’t follow any of those paths: Instead, she’s become the ultimate tragicomic actress. From working with her friend Mike White on “Year of the Dog” and “Enlightened,” to nabbing an Indie Spirit Award for her heart-wrenching role as a dying mother in “Other People,” she possesses the unique capacity to bring a depth of feeling to a look, or a sigh, or a smile that fades sharply into a wistful stare. It took a while for Hollywood to get the memo.

“Hollywood can put you in a box,” Shannon said in a recent interview. “I think sometimes when you do one thing, they think, ‘Oh, that’s all you can do.’ So I’m so grateful to Mike White … he gave me that first break where he wrote me a dramatic role.”

The role was Peggy in 2007’s “Year of the Dog,” in which Shannon plays a socially reticent woman grieving her beloved dog. The movie premiered at Sundance that year to positive reviews, with an ensemble that included Laura Dern, Regina King, John C. Reilly, and Peter Sarsgaard.

“Mike [White] really went to bat for me, because at the time I don’t think producers really wanted me in that role,” Shannon said of her friend. “They would’ve liked a more reliable person who was known in indie movies, but Mike was like, ‘Nope. I’m only gonna do the movie with Molly,’ and just totally went to bat for me. That was such a breakthrough for me, for Mike to believe in me that way and write that part for me, and I think it made people see that I could do dramatic roles.”

Shannon is quick to credit her collaborators for giving her opportunities to shine, most recently working with Madeleine Olnek, a scrappy micro-budget filmmaker who studied writing under David Mamet. With Shannon as the star of her Emily Dickinson romantic comedy “Wild Nights With Emily,” Olnkek is poised to see her biggest success. The two met in college at NYU, and it was in rehearsal with Olnek that gave rise to Shannon’s most famous character — Mary Katherine Gallagher.

Greenwich Entertainment

“Madeline was kind of like the midwife for Mary Katherine Gallagher,” said Shannon. Olnek was directing a comedy review show called The Follies, which starred a then-unknown Adam Sandler. During rehearsal one day, they did an exercise; Olnek was a big movie director and Shannon had to try to impress her to get the part.

“So I just walked through the door and I made up a character and I go, ‘Hi, I’m Mary Katherine Gallagher.’ And Madeleine was like, ‘Not impressed.’ And I’d have to come back and try to impress her more. And I guess then I fell in chairs, I don’t remember.”

Olnek wrote the review around her character, turning her into a murderer. “The show was so popular there were lines around the block at NYU. Before doing that comedy show, I was a very serious dramatic actress but then after people saw me in that show they were like, ‘You should be in Saturday Night Live!’”

Shannon’s silliest and most outrageous “Saturday Night Live” characters — from Mary Katherine Gallagher to Sally O’Malley — resonate deeply because they are grounded in universal human desires. Her characters vibrate with a wild sensuality; they mask their vulnerability with outlandish quirks; they’re driven by an intense desperation to be noticed, to be seen. They’re funny because they’re painfully real, entirely uninhibited, and because Shannon is so intensely committed. (You won’t find any clips of Shannon breaking character, that guaranteed-laugh cheat amongst certain SNL members). Her characters — and their catchphrases — are sketched as indelibly in the cultural memory as any originated by Chris Farley or John Belushi, and their enduring power comes from Shannon alone.

Not everyone saw it that way in the beginning. When Shannon brought Mary Katherine Gallagher to the male writers at “SNL,” they didn’t get it. “There was a guy writer, and he looked it over. He was in a pretty high position and he was like, ‘The reason this can’t work is, I don’t know, this isn’t really a joke. This’ll never work.’ And I was like, ‘But it is. It gets a laugh.’”

“And I’d just go and cry. I felt like I was way in over my head. You would just hear people typing and laughing and writing their script. And I was like, ‘They didn’t tell you it’s a writing job.’”

She eventually did get Mary Katherine on the air, and the rest is history. But her experience of going up against the male establishment is part of what drew her to “Wild Nights With Emily.”

“It made me really mad. I was feisty. So I related to her drive and her determination. She’s creative. Emily Dickinson wanted these poems published. She was hungry to be published. She was up against … these men that ran these papers and literary journals. I went through the same thing.”

Said Olnek, “So many of Molly’s personal qualities really illuminate who Emily Dickinson was.”

While Shannon may not be the most traditional choice to play Emily Dickinson, “Wild Nights With Emily” is not interested in the traditional view of the world’s most famous woman poet. An off-kilter comedy with some serious scholarship behind it, Olnek’s film radically upends the myth of Dickinson as a reclusive spinster who feared publication. It also shines a light on her nearly 40-year-long romantic relationship with her sister-in-law, Susan (Susan Ziegler).

“It’s so important to unlock the truth of that, about her story and her life and her love,” Shannon said. “And her primary collaborator was a woman. Her lover, Susan, and also creative collaborator … they were creative partners. Do you know what I mean? I mean, how is this story not told?”

Olnek moved mountains to get Shannon in the film by working around her schedule, offering to shoot in Los Angeles, and even casting her daughter in the role of Dickinson’s niece. After a recent screening, Olnek profusely thanked Shannon for starring in her little movie.

“The fact that Molly has played this role has allowed people, immediately, to understand so much more about Emily Dickinson and has made people interested in seeing a movie about Emily Dickinson, who would never go see a movie about Emily Dickinson, and would never be interested in reading her poems,” the director said.

Just as indie filmmakers like Olnek get a huge boost from a name talent like Shannon doing their films, Shannon recognizes that indie film affords her different opportunities. “I don’t think I would ever get offered to play a part like this in mainstream Hollywood.”

Accepting an award from the Provincetown Film Festival last summer, where “Wild Nights With Emily” played, she referred to this chapter of her career as only a lapsed Irish Catholic could: a “resurrection.”

“I can’t believe I’m in my fifties and I’m suddenly getting these amazing roles. … Why do I feel like I’m like Jack Nicholson in ‘Easy Rider,’ because it’s so fun? I couldn’t believe it was blossoming that way for me at this age.”

Comedy Central

Shannon is currently making waves on Comedy Central, working again with “Other People” writer/director Chris Kelly (a former “SNL” writer, though they never overlapped) on “The Other Two,” a half-hour comedy in which she plays a wide-eyed stage mom from Ohio whose son is becoming the next Justin Bieber. The show earned rave reviews for its first season, which covers topics from Insta-gays to viral fame with a sharp wit. The second season will see Shannon’s character, Pat Dubek, hosting her own talk show. She also co-stars on HBO’s “Divorce” opposite Sarah Jessica Parker.

On the film side, she played a rare misanthropic character in last year’s excellent dark comedy, “Private Life.” She also donned a habit as a lusty nun in “The Little Hours,” another period comedy similar in tone to “Wild Nights.” And who could forget her iconic performance as weepy arts and crafts counselor Gail in the cult comedy that never dies, “Wet Hot American Summer”?”

“There’s really great parts for women in these independent movies and in television,” she said. “There’s really an explosion. I feel like it’s really upped the game in writing. I don’t know, for me it feels like a whole new world.”

All the elements of a Shannon masterpiece are in her Emily Dickinson — the sexual appetite, the idiosyncrasies, the physical comedy. There’s a bit of Sally O’Malley in the way she wrestles with her petticoats, and a little Mary Katherine Gallagher as she gallops across the lawn after a late-night tryst. But it’s a stripped down, understated, and far more subtle Shannon. There is a seriousness about her performance that reflects the gravity of the story — the fact that Dickinson never saw her poems published, that she had to hide a lifelong partnership, and that most of the world still believes the lies told about her to sell books.

“We’re telling the truth about one of our greatest American poets. She was a trailblazer, a rebel, an LGBTQ hero,” Shannon said. “Yet we had these messages that she was some spinster recluse who didn’t want to leave her apartment and didn’t want to be published. These messages affect women now, women who are trying to get their voices heard and their voices out, but who are afraid. And so this story is just such an important story to tell. … Doing this type of movie reminds me what I like about acting. It’s so pure that it makes me feel like I’m going back to the beginning.”

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