Comedy that is actually funny plus romance that is actually sweet equals a sunny little valentine to brighten the winter doldrums. And — I can’t help saying it — Hugh Grant and Drew Barrymore go together like music and lyrics. Do I hear groaning? Okay, you see this film and see if you can resist getting a little gooey.

The movie opens with a brilliantly inspired parody of an 80′s music video, so flawlessly hook-ish and instantly familiar we’re sure we’ve seen it one some middle-of-the-night “I Love the 80′s”/”Where Are They Now” shows. It’s a little bit Wham!, a little bit Duran Duran. Alex (Hugh Grant) was once a part of this pop group, until it broke up and his bandmate went on to a successful career in recording and movies. Alex has been making a living by appearing in nostalgia venues like 20th high school reunions, state fairs, and amusement parks, booked by his manager, Chris (Brad Garrett, of “Everybody Loves Raymond”). He is currently considering a cable TV show called “Battle of the 80′s Has-Beens,” though he points out helpfully that his group broke up in 1992, which makes him a 90′s has-been.

Then Alex gets a once-in-a-lifetime chance at a comeback, if he can write a song for reigning pop princess Cora (newcomer Haley Bennett) in a couple of days. But he has two problems. First, he hasn’t written a new song in about 20 years. And second, he writes music only — he needs someone to write the lyrics. And who better to join forces with than the adorably ditsy young woman who is the substitute plant-water-er, Sophie (Drew Barrymore). Soon they are making beautiful music together.

The setbacks and sour notes that intrude are just barely troubling enough to keep the story going and to reinforce our relief when everyone settles down for a big, fluffy, happily ever after.

Grant and Barrymore are at their very best and the material is perfectly suited to their strengths. Grant’s self-deprecating delivery polishes the dry wit of his dialogue to a glossy sheen. Barrymore’s ditzily adorable way with a line is just right for a talented young woman whose confidence has just been shaken by a bad romance. The fabulous Kristen Johnson makes the most of her role as Sophie’s sister, the kind of fan of Alex’s pop group who had his lunchbox and wrote his name surrounded by hearts on her 8th grade notebook. If the portions of the story dealing with Cora and Sophie’s ex are weak, it’s just because the movie is too nice and its romantic leads too darling to skewer even the deserving. It’s as endearing as a pop song that still makes you smile, even 20 years later.

Parents should know that this is a milder-than-average PG-13. There is very brief strong language, some sexual references, a non-explicit sexual situation, and some dancing in skimpy clothes. There is a brief reference to drug and alcohol abuse, and some comic violence, including a punch.

Families who see this movie should talk about the music they like now and liked when they were younger and what has happened to some of the performers. Why do some performers seem to re-invent themselves to change with the times or to make the times change for them while others do not?

Families who enjoy this movie will also enjoy some of the other romantic comedies featuring Grant and Barrymore, including Never Been Kissed and Four Weddings and a Funeral (some mature material). They might like to explore some 80′s pop music from groups like A Flock of Seagulls, Duran Duran, Frankie Goes to Hollywood, and Wham! For a good real-life example of the way a big star adapts a song for her own style, listen to Madonna’s song “Don’t Tell Me” and the original version, performed by the songwriter Joe Henry as “Stop” on his album, Scar. Fountains of Wayne’s Adam Schlesinger, who wrote the song for this film, had an experience a little like that of Sophie and Alex when he entered and won the competition to write the title song for That Thing You Do.