‘Long Shot’: An improbably funny movie about the improbably funny hookup between Charlize Theron and Seth Rogen

The featured song in Long Shot is Roxette’s oldie “It Must Have Been Love,” ushered onto the charts when it appeared on the soundtrack for Pretty Woman.

That was the smash hit romantic comedy about a hooker (Julia Roberts) who ends up with a billionaire (Richard Gere), one of those occasional Hollywood movies that manages to successfully combine the ridiculous and the sublime.

And so it is with Long Shot, an improbably funny movie about the improbable hookup between an unemployed and unkempt journalist (Seth Rogen) and the poised, groomed-for-greatness Secretary of State (Charlize Theron) about to make a run for the presidency.

This is an intriguingly weird, gender inversion of the Cinderella fantasy at the root of Pretty Woman. Here, Theron is powerful alpha female Charlotte Field, on the cusp of being endorsed by her presidential boss (Bob Odenkirk) to be his successor.

At a posh party, she spots laid-off muckraker Fred Flarsky (Rogen), and recognizes him as the stammering nerd she used to babysit decades earlier. Flarsky is intimidated, but urged on by best bud (O’Shea Jackson Jr., good in support), he asserts himself, and a spark ensures.

Part of what Charlotte sees in Flarsky is her own pre-cynical, debate club, class president past — it’s a clever way for the movie to explain why these mismatched individuals connect across the socioeconomic/glamour chasm that makes the pairing so laughable and laugh-producing.

Also, Flarsky is funny — the role has been tailored to Rogen like a Bob Marley T-shirt with mustard stains — and as it happens, Charlotte is looking for a speechwriter to give her rather dry speeches some jokes.

Flarsky is hired over the objections of Charlotte’s protective number two (June Diane Raphael), and he is able to improve her speeches with one-liners. His contributions also make the candidate seem a little warmer, by suggesting the hopeful young woman Charlotte was before politics made her so pragmatic. Flarsky, for his part, learns why some jokes work for men but not for women, and the movie (cowritten by The Post’s Liz Hannah), in its own easygoing way, shows why politics is a minefield with more fatal footfalls for women.

The script places ultracompetent Charlotte in consistently amusing contrast to the out-of-his-element Flarsky — he panics during a rocket attack overseas, as Charlotte calms with breathing techniques learned from the Navy SEALs.

It’s familiar territory for Rogen, who riffs on work he’s done in Knocked Up and The Interview, but the movie really hinges on Theron’s ability to make us believe in Charlotte, and to keep us laughing while doing so. To that end, the movie provides yet more evidence of her skill and versatility.

It’s evidence that’s really piled up after she won her against-type Oscar playing a serial killer in Monster. In a string of movies with Jason Reitman and George Miller, she’s been angry, acerbic, physically imposing, in-charge, and funny (in Tully, one of my favorite movies from last year, she was all of those things) — all territory notoriously tough for women to navigate.

Here, she faces perhaps her toughest challenge of all — to be convincingly in love with Seth Rogen. It’s a long shot, but she pulls it off. Rogen, too, does some good work — his version of Roberts’ makeover scene in Pretty Woman is hilarious.

Long Shot. Directed by Jonathan Levine. With Charlize Theron, Seth Rogen, O’Shea Jackson, Bob Odenkirk, and June Diane Raphael. Distributed by Summit Entertainment.

Parents’ guide: R (language)

Running time: 1 hour, 55 mins.

Playing at: Area theaters