WARNING: SPOILERS

You’ve got to admire a sex comedy that can make Dan Savage squirm in his seat.

My main thought going into “The Overnight,” which closed the 2015 Seattle International Film Festival, was about the asterisk on the poster. I immediately thought it looked like Kurt Vonnegut’s illustration of an asshole from his novel “Breakfast of Champions.” But no way, right? I knew the movie was a sex comedy but I figured it wouldn’t reference Vonnegut (or assholes) so obliquely.

But that’s what it does. That’s what it is. (The poster has since gotten a sexier update: mouse over.)

It’s a simple premise. Alex and Emily (Adam Scott and Taylor Schilling) have recently moved from Seattle to L.A. for her job, but they feel isolated. Or he feels isolated. She, at least, has a place to go every day; he just goes to the park with their young son, R.J. But it’s there that they meet another father, Kurt (Jason Schwartzman), a porkpie-hat-wearing extrovert, who invites them to family pizza night, where, with wife Charlotte (French actress Judith Godreche), Kurt suggests they put the kids to sleep so they can continue their conversation like adults. But things get increasingly weird: They get stoned, he shows a breast-feeding video his wife starred in, he shows Alex his paintings of assholes, then he suggests they all go swimming in the pool and strips completely and dives in.

P.S. He’s hung like a horse.

Here’s the question: Is he just an extrovert interested in showing a Seattle couple a good time? Or is he interested in a good time?

It seems obvious he has ulterior motives but Alex doesn’t see them, even as Emily, and we, do. Alex’s continued naivete throughout the night is, in fact, the main false note in a movie predicated on delivering confessional truths. One assumes writer-director Patrick Brice needed to keep the show going, so he needed someone to be the naïve one, and Alex drew the short straw. So to speak.

That’s the part, I believe, that made Dan Savage—who moderated a Q&A after the screening—squirm. Not the fact that Kurt has a huge schlong and Alex has a little pee-pee; it’s Alex’s hot-tub admission that he has a small pee-pee—that his penis didn’t grow much after junior high, and that he and his wife have an unfulfilling sex life. That’s tough to admit. And baring your sexual soul to viritual strangers? Really? Although maybe it’s easier that way. Maybe that’s why we all go to priests and psychiatrists. A stranger is a buffer. Tell them anything and then continue with your normal, secretive life.

Still, Kurt and Charlotte are hardly pychiatrists, while the hot tub isn’t exactly a confessional.

Besides, you’d think with Alex’s particular secret, and with everyone stripping, he would be the first one to want to go, since staying would mean potential revelation. But he drew the short straw.

We wind up liking Kurt a lot more in the third act. For much of the movie, we assume he’s being nice to Alex to get to Emily; then we discover he likes Alex, meaning his motives aren't ulterior at all. Everyone, in fact, has a sexual secret or hangup. Alex has a small dick, Kurt likes Alex, Emily lusts after other men. Charlotte’s reveal is the oddest. She goes to Thai massage parlors and pays money so she can jack off fat men on tables. Really? In what world do hot French women need to pay money to give handjobs? And where do I volunteer for the experiment?

With its male full-frontal, and frank sexual discussions, “The Overnight” has potential as a cult movie. It’s certainly getting a lot of buzz. But I think there’s too many false notes on its path to the truth that we all have sexual hangups.

But I would love to take a poll of people exiting the film, particularly for gender reasons. After the SIFF screening, the women around me talked up how funny it was. That was their main thought: Funny. My main thought? Painful. But I seemed alone with this thought—and worried about what it said about me—until Dan Savage, with his first comment, set me free. Thanks, Dan. You’re right: It got better.