Apologies in advance: You’re going to have the “Titanic” theme song stuck in your head.

There’s nothing to be done about it, really. Just the mere mention of that behemoth of a boat movie is enough to dig the trill of the recorder out of the “1997” file in your memory and drop it directly into your ears.

“My Heart Will Go On” is not the best song of all time. “Titanic” is not the best movie of all time. But! But. Together they constitute the ultimate marriage of theme song and movie.

(Note: For level-playing-field purposes, musicals are excluded from this survey. Do not leave a comment about “Over the Rainbow.” “Over the Rainbow” does not qualify.)

Perhaps you remember the radio version of the “Titanic” hit that literalized this idea, the one with dialogue spliced between the verses. Now every time you hear the line “You are safe in my heart and my heart will go on and on . . .” you automatically insert the voice of LEO!!! — whose name in this context cannot be written without abusing the caps lock key and invoking multiple exclamation points — piping up out of the ether to say, “You jump; I jump. Right?”

“ ‘My Heart Will Go On’ is not just a song stuck on the end of a popular film,” said Jon Burlingame, a film music historian and author of “Sound and Vision: 60 Years of Motion Picture Soundtracks,” which includes a section on the “Titanic” music phenomenon. “You’ve got this haunting tune which goes throughout three hours of the film, and then it’s turned into a song at the end of the movie. You leave the film thinking about that, with that song resonating in your head.”

Maybe you hate it. Kate Winslet does, though fair to say it has a lot more baggage for her than it does for you. But maybe just the sound of that key change — you’re here, there’s NOOOOthing I fear! — makes you want to take a scalpel to your brain and carve out the spot where that song is stashed away. As soon as you think you’ve escaped it, there it is again: in the waiting room at the dentist’s office, on that “Lite FM” station you put on when you’re in the car with your parents, as inescapable a part of the American soundscape as the NBC chimes and the roar of the MGM lion.

Has there ever been a more fitting, or outrageously ubiquitous, theme song-to-movie match?

“The ones that immediately leapt to mind for me were ‘Doctor Zhivago’ in 1965 and ‘Love Story’ in 1970,” said Burlingame. Both were cases in which the instrumental music was so powerful, lyrics were added to create radio singles after the movies were released. A similar thing, incidentally, happened with “Titanic”; James Cameron didn’t want a theme song, so composer James Horner “quietly employed a lyricist, Will Jennings,” said Burlingame. Horner had Celine Dion record a demo and persuaded Cameron to include it in the film.

“If you go even farther back, you can go to ‘Casablanca,’ ” Burlingame added. “You can’t think about it without ‘As Time Goes By.’ ” The key ingredients to these power song-movie couples: “an epic love story [often set] against the backdrop of a huge historical event.”

More recent contenders, from “Mrs. Robinson” and “The Graduate” to “(I’ve Had) the Time of My Life” and “Dirty Dancing” don’t have high enough stakes to compete. Every time you hear “My Heart Will Go On,” you know Dion is supposed to be singing about a love that outlived her beloved. “Time of My Life” is about a girl who had the Best Summer Ever! with a hot dance instructor and, in the process, learned to overcome stage fright.

The Bodyguard” brought the masses the insta-epic Whitney Houston rendition of Dolly Parton’s “I Will Always Love You.” But a superior song does not a superior match make. It’s not like every time you hear Houston hit the high notes you think, “Oh, that’s the theme from ‘The Bodyguard!”

Since the 1970s, nothing has come close to the “Titanic” song, which propelled the movie’s soundtrack to No. 1 on the Billboard charts and kept it there for 16 weeks. Dion’s album, “Let’s Talk About Love,” also included the hit single and, unsurpisingly, also made it to No. 1. “My Heart Will Go On” and “Titanic” are inextricably linked, like Walt Disney and Mickey Mouse.

“Here’s what I love about it,” said Burlingame. “It’s about the power of music and image. When intertwined, it’s greater than the sum of the parts. . . . That’s certainly what happened with Horner’s score for ‘Titanic.’ ”

As for the “My Heart Will Go On” haters? “Let’s face it: they may hate it, but everybody bought it.”


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