Nick Milligan made headlines in February when he found the similarities between his book, Enormity, and the premise of the trailer for the film, Yesterday, "too large to ignore".

Yesterday opened in cinemas on Thursday.

"I was a little numb going into the film, I wasn't sure if I wanted the movie to be amazing or bad," Mr Milligan said. "While the concept and general plot are the same, the tone of the movie couldn't be any further away from Enormity. Yesterday is a very cute, very family friendly movie that is as much a love story than it is about someone stealing the Beatles' music."

Mr Milligan began writing Enormity a decade ago, and published it as an ebook in April, 2013. In Enormity, the main character - Jack - finds himself on a planet almost identical to Earth, with a race of humans that seem to have evolved in parallel to us.

"He passes off classic music as his own material, including that of The Beatles, and the story explores the consequences of that lie," Mr Milligan said previously.

In Yesterday, the protagonist - also Jack - has an accident and wakes up in a version of Earth in which The Beatles have never existed, except in his mind.

"He passes off their classic music as his own material, and the story then explores the consequences of that lie."

Mr Milligan, who is also a movie reviewer, learned of the new Danny Boyle-directed film in September last year. When he read the premise of the Richard Curtis screenplay, his "heart sank".

But it was only once he had seen the trailer, learned the protagonist's name was also Jack, and saw the trajectory of the character's arc that he felt the similarities were too large to ignore.

"Having now seen Yesterday, I am a little relieved," he said. "Yes, Yesterday essentially has the same plot as Enormity to a point, but my book goes deeper into the potential power of the music. Jack's lie has much darker consequences. Mine is not really a romantic story, and far from family friendly. So while the plot is the same, the tone is vastly different."

Mr Milligan admitted he was not the "target audience" for Yesterday.

"I say this knowing that it will sound like sour grapes, but I didn't think it was a great film," he said.

"It's certainly the most cute and saccharine movie to which Danny Boyle or Richard Curtis have put their name, and I think a lot of people will find it charming.

"But I also felt it celebrated the Beatles' greatness in a fairly trite way, telling the audience how great the Beatles were rather than showing it in a meaningful way."

Enormity is available as a paperback and ebook via Amazon.

Yesterday is showing at cinemas now.

Newcastle Herald