The MarvelsSave

Opening cold open. The Kree homeworld of Hala — once a thriving Kree empire — is dying. After Carol Danvers killed the Supreme Intelligence in Captain Marvel (2019), the resulting Kree civil war and the Supremor's absence have caused Hala's red sun to slowly burn out. The atmosphere has lost most of its breathable air. The Kree people have been dying for thirty years. Dar-Benn (Zawe Ashton), a Kree warrior and high priestess, has assumed the regency. She blames Carol Danvers personally for Hala's slow death and has been hunting for the Quantum Bands — twin cosmic-bracers that, when united, can manipulate the multiversal Jump Network and pull resources (sunlight, water, air) from one planet to another via dimensional portals. She has just retrieved one Quantum Band from a planet she invaded. She slips it onto her wrist.

Earth. Jersey City. Kamala Khan (Iman Vellani), age 16, the Pakistani-American superhero from the Disney+ Ms. Marvel (2022) TV series. Kamala has been wearing the second Quantum Band as a family heirloom-bracelet for months without knowing what it is. Kamala has been quietly active as Ms. Marvel — using cosmic-bracelet-energy abilities — and idolizes Carol Danvers as her hero. Her parents Yusuf (Mohan Kapur) and Muneeba (Zenobia Shroff) and her older brother Aamir (Saagar Shaikh) have been struggling to support Kamala's secret superhero life.

Captain Marvel in space. Carol Danvers (Brie Larson) is in deep space — she has been a self-imposed cosmic exile for almost five years. She has not visited Earth except briefly for the Snap-reversal in Endgame (2019). She has been doing freelance cosmic peacekeeping work, deeply burdened by guilt about Hala's slow death (which Carol still doesn't fully understand was her fault). She lives alone on her flagship.

SABER space station. Monica Rambeau (Teyonah Parris), the former S.W.O.R.D. agent and now-cosmic-energy-empowered hero from WandaVision (2021), has been working at the SABER orbital station as Nick Fury's science liaison. Her superhero codename is Photon. She can phase her body into pure light energy. She has not spoken to Carol Danvers since her mother Maria Rambeau died of cancer between Captain Marvel and the events of WandaVision. Monica has been mourning her mother and has been resentful that Carol — once like an aunt to her — disappeared into space and never visited.

The entanglement. Dar-Benn activates her Quantum Band to open a jump-point in the cosmic network. The activation causes an immediate cosmic-physics anomaly: Carol Danvers, Monica Rambeau, and Kamala Khan — all three of whom share a unique cosmic-energy signature — suddenly find themselves entangled at the quantum-particle level. Whenever any one of the three uses her cosmic-light powers, all three swap physical locations simultaneously. Carol in deep space teleports to Kamala's bedroom in Jersey City. Kamala teleports to SABER station. Monica teleports to Carol's flagship in deep space. They have no idea why this is happening.

Comedy chaos. The early film plays out as a slapstick comedy with the three heroes constantly swapping locations against their will, trying to coordinate via comms while being randomly teleported into each other's positions. Kamala materializes in the middle of a deep-space dogfight, fires off random energy bursts, then teleports back to Earth. Monica appears at the breakfast table of the Khan family in her SABER uniform and is force-fed Pakistani breakfast by Muneeba Khan. Carol Danvers, in her uniform, teleports onto a New Jersey suburban couch in front of Yusuf Khan and his wife. The Khan family — completely starstruck — invite Captain Marvel for chai. The early film is genuinely funny.

Tarnax. The three heroes finally meet face-to-face on Tarnax — a Skrull refugee planet where Nick Fury (Samuel L. Jackson, in his Skrull-allied diplomatic role) is operating an off-Earth Skrull-protection base. They debrief. They realize the cosmic entanglement is causing all of this. They learn from Fury's intel that Dar-Benn is using the Quantum Band to attack three different planets that Carol has personal ties to — Aladna (a planet where Carol had been briefly diplomatically married to a prince during a previous cosmic mission), Tarnax (Skrull refugee planet), and a third planet she has not yet attacked.

Aladna. The trio (now organized as Captain Marvel, Photon, and Ms. Marvel — "the Marvels") fly to Aladna, an aquatic planet whose inhabitants communicate exclusively through music — every dialogue line on Aladna is sung in operatic style. Carol had been briefly married to Prince Yan of Aladna in a diplomatic ceremony three years earlier. She had never actually consummated the marriage (it was strictly political). The Aladna sequence is the film's most-divisive set piece — a six-minute musical number where everyone, including Brie Larson, sings their dialogue in elaborate operatic style. Some critics loved it, most audiences hated it. Then Dar-Benn arrives. She uses the Quantum Band to drain Aladna's atmospheric water completely. The planet's oceans evaporate in three minutes. Trillions of liters of water are teleported to dying Hala. Aladna's surface dries to bone. The Aladna people retreat to underwater cave systems. Dar-Benn jumps away.

Carol's Hala flashback. The team chases Dar-Benn through cosmic jump-points. During a quiet moment on Captain Marvel's flagship, Carol finally confesses what happened to Hala. She had not known when she killed the Supreme Intelligence that the Supreme Intelligence had been the only mechanism maintaining Hala's red sun's stability. The Supremor had been a literal artificial intelligence that managed the Hala star's hydrogen-fusion rate. When Carol killed the Supremor, the sun's fusion went out of control and the star began burning out. She had inadvertently doomed Hala's entire civilization. She has been carrying that guilt for decades. Monica, who has been resenting Carol for her absence, finally understands. She forgives her.

Final battle. Dar-Benn's plan is to use the second Quantum Band (still on Kamala's wrist) combined with her own to create a permanent dimensional-rip between Hala's universe and Earth's universe, draining Earth's sun completely to refuel Hala's. Kamala figures out how to make Dar-Benn touch the second band by herself. They lure Dar-Benn into a confrontation. Dar-Benn touches the second band. Both Quantum Bands ignite simultaneously. The cosmic dimensional rip begins to open. It would consume Earth's sun in seconds. Then the cosmic-entanglement that linked the Marvels suddenly amplifies — all three heroes channel their light-energy together to hold the rift closed.

Monica's sacrifice. Monica Rambeau realizes that the only way to seal the rift permanently is to use her body's light-energy phasing ability to push the dimensional aperture closed from the other side. She walks through the rift voluntarily. She turns to Carol and Kamala. She says goodbye. "I'll see you both. Maybe in another world." She phases into the rift and seals it from her side. The rift collapses. Monica disappears into the closed dimensional aperture. She doesn't come back.

Aftermath. Dar-Benn's Quantum Band is shattered. Dar-Benn herself is exiled to deep space without her power source. Carol Danvers and Kamala Khan return to Earth. Kamala arrives back in Jersey City at her family kitchen table. Her mother hugs her. Then the unexpected coda: Kamala's bedroom doorbell rings. Kamala goes to answer it. Standing on her front porch is Kate Bishop (Hailee Steinfeld, reprising her role from the Disney+ Hawkeye (2021)). Kate has been recruiting young heroes for a team. "Hi. You're Ms. Marvel, right? I'm Kate Bishop. I'm putting together a team. You in?" Kamala lights up. The Young Avengers are being set up.

Mid-credits. The dimensional rift Monica fell through opens onto a parallel universe. Monica wakes up in a medical bay on a planet that looks almost like Earth but slightly different. A face leans over hers. It's her mother. Maria Rambeau, alive and well, in a uniform. "Monica? What are you doing here?" In this alternate universe, Maria Rambeau is alive. She's also wearing the Captain Marvel costume — she's the alternate-universe Captain Marvel. Beside her stands a tall blue-skinned humanoid in a tweed jacket — Hank McCoy, a.k.a. Beast (Kelsey Grammer, reprising his X-Men: The Last Stand role for the first time in seventeen years). The blue-furred X-Man is in the alternate universe Monica has fallen into. The MCU has officially introduced its first X-Men variant. Cut to credits.

Post-credits. Static. Monica is in another dimension. The X-Men exist in that dimension. The post-credits scene is a literal black-and-white still image of Beast and Captain Marvel-Maria standing over Monica's hospital bed. Hank McCoy's voice: "Welcome to Earth. We have much to discuss." Cut to credits. The MCU's X-Men crossover has officially begun.