British singing sensations Adele and Sam Smith could soon bless the world with a collaboration - but not for the reasons you think.

A bizarre theory that the singing powerhouses are, in fact, the same person is making the rounds online after sharp-eared Twitter user @jesse21valona shared a video clip which revealed that when Adele's hit track Hello, is played on vinyl and slowed down on a record player, it sounds like it is Smith singing.

The video captioned: "Did you know that when you slow down Adele it's actually Sam Smith" has been watched more than four million times and garnered almost 126,000 retweets since it was uploaded on 5 February.

We have all heard theories that old rock records, when played backwards, contain secret messages so it is not surprising that fans are agog with the theory that we have one shape-shifting superstar on our hands.

"It all adds up. I just googled to find a picture of them together. There is none!" one person said. "I think they are the same person!"

Another added: "@Nutella_phan commented, "WHAT WHAT IS THIS MAGIC."

@MegGriessel wrote, "Mate. they're never seen together at the same event. they're British legends, sing the same genre. legit I'm telling you. *x-files theme tune*"

Sam Smith previously told Rolling Stone that he had grown exasperated with the constant comparison with Adele, saying: "It just annoys me that people can't digest two pop stars singing really personal songs who don't look like normal pop stars."

One thing they definitely have in common is that they have both earned best original song Oscars for their respective Bond themes, Skyfall and Writing's On The Wall.