Here's the premise. Jack (Himesh Patel) is musician is struggling to make it. He hits a low point playing in front of four disinterested kids at a fair. As he mulls over whether or not it's all worth it, a cataclysmic power outage causes the whole world to suffer from a collective case of amnesia. Except for Jack.
As the power outage takes place, Jack gets hit by a bus, perhaps sparing him from amnesia. Upon getting released from the hospital he's gifted an acoustic guitar from his girlfriend (Lily James) and begins playing The Beatles "Yesterday."
After he's done playing, his friends look on in astonishment asking "when did you write that?"
Jack responds by telling them "I didn't write it, Paul McCartney wrote it. You know, The Beatles."
His response mystifies the group indicating they've never heard of The Beatles. When Jack presses them about not knowing one of the greatest songs of all time, they respond by telling him it's not Coldplay's "Fix You."
From there Jack goes on to confirm that the world has no idea who The Beatles are with the group and all of their members being wiped from Google. Predictably, Jack goes on to become an international superstar by performing Beatles songs with everyone thinking he wrote them.
Also, Ed Sheeran is in the film.
I don't know what to make of the movie, but it was wildly entertaining throughout the trailer and has a plot so ridiculous it absolves it from ridicule.