WARNING: The following article contains spoilers for Yesterday, in theaters now.

Yesterday features a delightful surprise appearance, and we're not talking about Michael Kiwanuka, James Corden and Ed Sheeran, who came on board to play themselves for Danny Boyle's love letter to the Beatles (despite Sheeran's parody of himself being comedy gold). No, we're talking about one of the movie's final scenes that came out of nowhere to take our breath away.

The premise of the movie is that a struggling musician named Jack Malik wakes up one day to discover the Beatles have somehow been removed from his reality. Everything else about his life is largely unchanged. Yesterday isn't terribly preoccupied with the Butterfly Effect -- but the absence of the Beatles from the pop culture landscape inspires him to take advantage of being able to release their songs as his own. He spends most of the movie on a meteoric rise to fame that sees him make friends with a not-so-humble Ed Sheeran and also develop paralytic guilt at absconding with the legacy of artists he considers sacred.

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Eventually, we discover that he wasn't the only one to remember the Beatles that morning, and two superfans travel to one of Jack's concerts to confront him... with gratitude. They're just adorably pleased someone who could sing decided to bring Beatles' music back to the world. Then they all sing "Yellow Submarine" together and the anonymous duo leaves him with John Lennon's address.

That's right, the Beatles don't exist, but Lennon apparently does. Jack uses the address and finds himself at a humble seaside cottage, and when he knocks on the door, he's greeted with an aged, but unmistakable John Lennon. It's also an aged and unmistakable Robert Carlyle, which makes this twist of a sort doubly nostalgic and resonant at least for Danny Boyle fans. And this is no digitally rendered Lennon voiced by Carlyle -- prosthetics and practical effects are used with surprising efficacy to convey Lennon's recognizable features, aged and laid upon Carlyle's own visage.

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Representing a figure as, frankly, hallowed as Lennon with makeup presented a risk for huge backlash if the result turned out in any way comical or fantastical. Luckily, it doesn't -- Jack and John's strange meet-cute is one of the best scenes in the film.

John is a placid 73-year-old widower who's perplexed at Jack's sudden appearance but has a cup of tea with him anyway, of course. Jack asks him if he's had a happy life, and John confirms that indeed, he has. He's been privileged do a job he enjoyed and to have been married to a woman he loved (before you ask, we didn't spot any Yoko pics in John's house, but it doesn't mean they weren't there!).

That revelation makes for a bittersweet moment in Boyle's optimistic fantasy. Jack's spent much of the movie trying to capitalize on the Beatles' work while simultaneously remaining in shock at the fact of their total erasure. The audience also wrestles with the idea of a world without the Beatles, but this scene between Jack and John illustrates a hugely positive thing that could come out of a world without the Beatles' music: John Lennon getting to live a long and peaceful life.

This moment is important because Yesterday doesn't reset its timeline at the end of the film. The world doesn't revert to the one Jack was born in, but it does give us the gift of a little spot in the multiverse where the Beatles don't exist, but John still does. And ultimately it allows Jack to end the movie leading by selfless example as he apes his idol, returns to a simpler life and gives away the music for free. And a world where people say no to the kind of commercial interests that come slavering Jack's way doesn't sound too bad at all.

Directed by Danny Boyle from a story by Richard Curtis and Jack Barth, Yesterday stars Himesh Patel, Lily James, Ed Sheeran and Kate McKinnon. The film is in theaters now.