Cooper Hoffman and Alana Haim make smashing debuts in Paul Thomas Anderson’s “Licorice Pizza.” (Metro Goldwyn Mayer Pictures Inc./The Minnesota Star Tribune)

People fall in love all the time at the movies, but it's rare to see the process of falling in love, a phenomenon that "Licorice Pizza" is all about.

Like most romances, things don't begin well in Paul Thomas Anderson's 1973-set comedy/drama. Gary (Cooper Hoffman, son of Philip Seymour) is an absurdly confident high schooler who hits on Alana (Alana Haim), who's assisting a guy taking class pictures at his school. She rejects him but he tells his brother, "I met the girl I'm going to marry."

Lots of people say that in the movies, too, but we don't find out if marriage might happen in "Licorice Pizza," which doesn't get that far. Episodes unfold, connected only because they involve Gary or Alana and because they bring the two closer to the romance that this charming, observant movie makes us hope they'll find. Or at least the possibility of romance, since there's an age difference and who knows if they're perfect for each other?

Hoffman and Haim make their movie debuts here, and it's rare for a major movie to rest on the shoulders of such unfamiliar actors. (However, Haim is well known as a member of the band Haim, for whom Anderson has directed several videos; her sisters/bandmates and parents play her family.) But he was smart to cast these newcomers, as they bring no preconceived notions, and are so likable, distinctive and intelligent.

Gary could come off as a blowhard. But Cooper's sunny, dogged quality is irresistible, similar to a puppy who persists until even the most resolute dog disliker pets him. He deftly handles his formal dialogue, which suggests he learned seduction from screwball comedies. Haim is pricklier but Alana's insistence that she's on exactly the path she's supposed to be on makes her a character to admire and even love.

The movie title refers to an actual '70s record store in Southern California, where the film takes place, but what is "Licorice Pizza" about? Incidents are more important than plot. Gary plows into unlikely business ventures, which include trying to capitalize on the waterbed craze and doing PR for a racist Japanese restaurant owner (who, despite controversy that suggests otherwise, is depicted as unfunny and cruel).

Meanwhile, Alana becomes active in politics and assists Gary on such missions as delivering a waterbed to the home of Barbra Streisand and her psycho boyfriend Jon Peters (played by Bradley Cooper, who's having way too much fun skewering a guy he probably dealt with while making "A Star Is Born"). There's also a brush with a faded actor (Sean Penn, channeling William Holden) that has little to do with Gary or Alana.

Even that potentially distracting scene feels like it belongs in "Licorice Pizza." Everything does. We see so many movies that seem hastily or badly put together. So it's an absolute pleasure to spend time with Anderson's sensibility, which finds shape and texture in every moment. The movie is so beautifully made that it feels like it's using all of your senses at once.

Like "Boogie Nights," another perfect movie from Anderson, "Licorice Pizza" shows life on the fringes of '70s Hollywood. But unlike "Boogie Nights," it's a song of innocence. Energy and youth burst from every frame, with its characters often shown running to their next adventure. That's how it ends, in fact. Alana is running at full speed toward the left side of the screen and Gary is running toward the right side. Toward each other.

'Licorice Pizza'

**** out of 4 stars