Drew Barrymore stars as an aspiring songwriter in Music

Love Hugh Grant. Love Drew Barrymore.

And if they don’t burn down the house with any sparks they set off in “Music and Lyrics,” their Valentine to moviegoers, they at least make it amusingly watchable.

It’s about songwriting, has-been pop stars, the Britney-Christina-Shakira bellydancers of girl pop and not much else. Any romantic or personality “issues” it reaches for it never quite grasps.

But if you get any pleasure from watching two of the best romantic comedy actors of the past 20 years do their thing and give their all, then this is the date movie for you.

Go if for no other reason than you may never have the chance to see either of them sing again.

In a spot-on and hilarious opening, we see an ’80s Brit-pop band in the Spandau Ballet/Wham! mold bounce through a video of their tune “You are Silver, I am Gold.” They were called PoP. And Alex (Grant) used to be their keyboardist, composer and rump-shaking backup sex symbol.

The band broke up. The lead singer’s a huge Hollywood star. Alex is stuck doing county fairs, amusement parks and high school reunions, singing and shimmying in front of shrieking 40somethings to a tape-recorded music track. He’s being recruited for “’80s Has Been” boxing matches.

Then, his manager (Brad Garrett, funny) wins him a second chance. The pop-star of the moment, Cora (Haley Bennett, play-acting at being dim and inexpressive, we hope) was a fan as a toddler. She wants Alex to write her a new break-up-with-my-beau tune, with this title, “Working Our Way Back to Love.”

By Friday. Big problem.

Bigger problem: He doesn’t do lyrics.

“I once rhymed ‘you and me’ with ‘autopsy.”‘

He tries out a professional lyricist, and they don’t click. But the dizzy blonde who comes in to tend to his plants (Barrymore) is a lyricist savant.

“You are Cole Porter in panties!” Alex enthuses, before speculating on the sort of underwear Porter actually wore. He needs her help. She’s reluctant.

But Alex wins Sophie over, and they get down to it, him noodling at the keyboard (Grant really plays) and her nervously clicking her pen.

“We’re not writing the Jupiter Symphony here,” he whines. “It’s a song for someone whose last hit was ‘Welcome to Booty-town.”‘

They work away, and take a tumble with one another in the process. She’s never gotten over the jerk college professor (Campbell Scott) who used her, tossed her aside and then wrote a novel about someone just like her that’s become an embarrassing best seller. He has self-esteem issues of his own. Can love find a way?

The movie’s sense of late ’80s pop is almost as accurate as its feel for early ’80s romantic comedies. This is “Best Friends” (1982) without enough gags to sustain it, a comedy built on the pre-“Four Weddings and a Funeral” business model.

Sandra Bullock tied her career to writer-director Marc Lawrence until that sad little nothing “Two Weeks Notice,” and she wisely palmed him off on Grant, who deserves better. Still, this is no “American Dreamz.” He’s charming as ever, and he hurls himself into the part. Singing, hip-shaking, tossing off the quips, he’s almost the Hugh of old.

Barrymore, playing yet another lovelorn waif, does something she wouldn’t do even when Woody Allen asked her to in “Everyone Says I Love You.” She sings.

But if “Music and Lyrics” were a song, you’d have to say it doesn’t have a good beat, though it is easy to dance to.

And you’ve got to appreciate the guts of an actor willing to sing, dance, and willing to say, even in character, “I’m a happy has-been.”