Correction: A previous version of this article misstated the last name of a midshipman from Sun Valley, Idaho. She is Ashleigh Share, not Ashleigh Shane. This version has been corrected.

There are no words to adequately describe what happens on Halloween weekend in the chapel of the United States Naval Academy.

But let’s try some out: Bizarre. Bonkers. Bananas. Transfixing. Transcendent.

Underneath the chapel’s majestic red-lighted dome and between ramparts of darkened stained glass, dozens of midshipmen perform their Halloween/All Saints’ Day concert as if directed by a tag team of Liberace, Milton, Twyla Tharp, Admiral Farragut and the pope. The mids are backed by nearly 16,000 gut-throttling organ pipes and splashed with 127,000 watts of spinning rock-concert lighting.

At the top of the variety-show spectacle, chanting midshipmen dressed as monks carry the organist up the aisle. In a casket.

What follows for the next 80 minutes is like a Meat Loaf music video, except when it’s like a glee club pageant. It’s Grand Guignol and Gershwin. Scripture is quoted. Jim Henson is invoked. Phantoms of the opera sing and swish from crevices and catwalks. A spotlight follows a giant fake bat as it zip-lines the entire height and length of the chapel. A barbershop quartet sings the theme to “The Addams Family” as Cousin It staggers from the altar to the nave.

Over its 16 years, the Naval Academy’s Halloween concert has become a spine-tingling, jaw-dropping, head-spinning, cringe-inducing, heart-soaring tradition of camp and kitsch and patriotism and piety that draws a rapturous sold-out crowd of 4,000 over one weekend.

It’s — well, what is this show? And why do the good people of Annapolis flock to it?

Says Ashleigh Share, a senior engineering major from Sun Valley, Idaho, “It’s the triumph of good over evil, light over darkness, with ‘Be Our Guest’ as a transitional song.”

There you have it. During the concert, Share, 21, dances through the pitch-black chapel in a black bodysuit twined with battery-powered neon wire as the fingers of organist Monte Maxwell somersault through Bach’s Toccata and Fugue in D Minor.

Did we mention that this concert is also like a Pink Floyd laser show, except when it’s like a baroque Mardi Gras (except when it’s like a somber Changing of the Guard)?

All performing arts on the Yard are extracurricular, so the concert draws mids who enjoy exercising both their left and right brains outside the parameters of academics and military duties, Share says. It’s been this way on the Yard since 1997, when Maxwell, the director of chapel music, performed one organ-and-light show for 300 people using 20 midshipmen, 14 colored lights and a fog machine. The next year, 3,000 people crammed into the chapel. The year after that, a second show was added, with Maxwell providing all the musical accompaniment (from memory) through the organ’s various audio functions. The spectacle, which is funded by ticket sales (in the tens of thousands of dollars), has ballooned under Maxwell’s guidance — “It really is a journey that carries you through the gamut of emotion,” he says — and has succeeded by virtue of the midshipmen’s commitment and skill.

A half-hour before Friday’s show, the shadowy crypt of American Revolution hero John Paul Jones echoes with the warm-up scales of golden-voiced sopranos and baritones. The crypt, underneath the chapel, doubles as a green room and backstage area, and for this past weekend is hazed with hairspray and stocked with costume racks and makeup vanities. Caped midshipmen sing and sashay their way down marble staircases and through catacomb-y corridors.

“I went to high school in San Francisco, and people were very free there, always hugging, and it was a different culture than” at the academy, says Sam Strelkoff, 21, a senior majoring in computer science and information technology. “The first time someone hugged me here was after the Halloween show, and I thought ‘Oh, I’m home.’ ”

Strelkoff, his face painted into a white mask, will belt “The Phantom of the Opera” at the top of the show from a catwalk in the chapel’s dome.

Adults and children are in line outside the chapel two hours before showtime Friday, as a warm dusk settles on the Yard. Strobe lights pulse through the chapel’s windows, making the building look like the exterior of Frankenstein’s lab. Mids dressed as gargoyles slink around the chapel steps and scare the dickens out of unsuspecting Annapolitans. A mid costumed as a black-winged Angel of Death, bathed in red light, lurks on a pedestal in front of the chapel’s imposing doors, which open to the giddy throng about 7:30 p.m.

Under the chapel, concert director and junior midshipmen Christian Freudenberger speaks into his headset — “Can someone bring some electrical tape down to the crypt?” — as he dodges flatware practicing the lyrics to “Be Our Guest.”

Upstairs, shortly after 8, the organ explodes with the opening arpeggios of “The Phantom of the Opera” as fog pours off the altar and light beams swing through the air. Caped singers appear one by one throughout the chapel, culminating in Strelkoff’s strident baritone blaring from over 100 feet above the organ.

From there, the concert veers among tones and musical numbers. Mids wearing giant skeleton heads race around the nave as Maxwell plays Wagner’s “Ride of the Valkyries.” Out of nowhere, Norman Bates’s mother sprints down the center aisle, stabbing what looks like an oversize fork at the audience. Then a mid wrapped in a pink feather boa plays the saxophone to the “Pink Panther” theme as a group of Inspectors Clouseau poke around the nave, trailed by spotlights.

“Be Our Guest” is the showstopper. Mids on stilts totter through the aisles holding giant tea cups and cutlery. Mids wearing gold-painted candelabra helmets twirl. Giant cardboard salt and pepper shakers sprinkle confetti from the dome catwalk.

Then senior Hunter Gibson, wearing overalls and a mournful expression, trudges up the center aisle bellowing “Ol’ Man River” to thunderous applause.

It’s all very stirring and weird. In between musical numbers, the curmudgeonly Muppets Waldorf and Statler trade cynical patter from the pulpit. Because why not? The concert — which elicits goose bumps and raises eyebrows, sometimes simultaneously — has refined a distinct art form: the Great American Hodgepodge, in which all available notes are sounded, in which a cacophony of cultural nostalgia somehow becomes a harmonic symphony of national sentiment.

Immediately after a flapperlike rendition of “I Got Rhythm,” the chapel goes dark and a godlike narration resounds over the loudspeakers:

“We have been very blessed as a nation. So many have gone before us, making the ultimate sacrifice for our freedom. . . . There is a single candle in this building that serves as a remembrance to those who are prisoners of war or are missing in action. . . . Tonight we light this candle, paying homage . . . to those with us and those who have gone on before us.”

Maxwell begins playing Samuel Barber’s “Adagio for Strings” — a.k.a., the saddest music ever written — quietly at first, then building in volume as a lone midshipman in white uniform carries a candle through the center aisle of the chapel. A rolling carpet of theatrical fog follows him. Spotlighted, he looks like a ghost.

Audience members sniffle and dab their eyes as the organ transitions to the melody of “The Battle Hymn of the Republic.” The spotlights find soloists, positioned around the chapel in their choker whites, as each sings a verse of the hymn. By the time Sam Strelkoff bellows “Let us die to make men free!” from the altar, every midshipman involved with the concert has surrounded the audience on the aisles, and sings the “Glory, glory, hallelujah!” refrain together. At the song’s final chord, a massive American flag unfurls from the chapel dome.

As Ashleigh Share says, and as Maxwell intends, the concert is — in its own strange and glorious way — a celebration of that timeless narrative of good over evil, light over darkness, even when the ultimate sacrifice is involved.

This time next year, Share, having danced her last neon-bodysuited dance in the concert, might be in California on a surface-warfare tour. Strelkoff might be stationed in a submarine, a world away from wearing a mask on the catwalk of the chapel. But right now they are bowing with their classmates to a standing ovation from the crowd, which will exit the chapel to find a midshipman dressed as a haloed white seraph standing on the pedestal where the Angel of Death used to be.