A theory about classic musical Grease posted on Reddit three years ago has resurfaced on social media, giving fans a lot to think about. The fan theory, concocted by user ‘atomicbolt’, claims that main characters Sandy and Danny are actually dead and the whole movie is just ‘a drowning woman's coma fantasy’.

John Travolta and Olivia Newton-JohnGrease stars John Travolta and Olivia Newton-John

Atomicbolt was wondering, how did Sandy and Danny’s red convertible manage to fly into the sky at the end of the movie?. While the question is certainly valid, the user came up with their own theory, that gives the high school musical a very dark twist.

‘At the start of the film, we see Danny and Sandy meeting on the beach,’ they wrote. ‘Later Danny explains through song that they first met when Danny 'saved her life - she nearly drowned’. According to atomicbolt, Sandy did actually drown on the beach that day and everything else is just her fantasy.

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'As she drowned, her brain deprived of oxygen, she had a vivid coma fantasy involving her summer fling Danny, where they shared a magical year of high school together,’ they continued. 'The visions get increasingly outlandish as time passes, until finally, as Danny desperately tries to resuscitate her on the beach, she sees herself flying into Heaven in her dying moments.’

'The entire movie was a drowning woman's coma fantasy.’ While most users rubbished the theory and one bright sparked simply wrote: 'Explain Grease 2’, another user, Randomd0g, chimed in with their, even darker take.

‘I have a similar one to this which makes it so it's not just a complete "all in her head" theory,’ they wrote. ‘Sandy kills herself towards the end of the movie and the entire last scene is her dying thoughts (and/or a dream sequence of some kind)’.

As evidence Randomd0g writes that the last line of song ‘Look at me I'm Sandra Dee’ is "Goodbye to Sandra Dee” and adds that everything that happens in the last scene is just a little ‘too perfect’. ‘Danny and Sandy are back together despite everything,’ they write.

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‘Rizzo SUDDENLY isn't pregnant AND Kenickie suddenly decides that he actually loves her, the geeky kid gets onto the sports team, EVERYTHING is suddenly ok, just the way that sweet, innocent Sandy would have wanted it to be’.

They then added: ’in the last shot of the movie, she flies up to heaven with her dream boyfriend in her magic flying car’. While both theories aren’t exactly plausible, they have left us reflecting on what a strange movie Grease really is and wondering, how does a convertible just take off into the sky?