It was a trailer for High School Musical that inspired Ryan McHenry.
The Scottish director thought the only way he could enjoy the film was "if the whole cast was consumed by zombies."
This gave rise to an idea of the movie Anna and the Apocalypse, which is released in cinemas on Friday – more than three years after Dumfries, 27, died of cancer.
Director John McPhail has embarked on a project to get to the big screen.
"He was a brainchild Ryan McHenry," he said.
"Ryan wrote and directed a short film called Zombie Musical, which won the Scottish new talent of Bafta.
"Then he's going to develop Black Camel into a feature film."
However, Mr. McHenry, the man behind the award-winning Ryan Gosling Will not Eat His Cereal, was unable to complete the project.
"Through design and development, Ryan was diagnosed with cancer and sadly died in 2015," said Mr McPhail.
"His long-time friend and producer Naysun Alae-Carew did not want the project to disappear and wanted to preserve such a memory, so he started looking for directors.
"They were looking at horror directors and music directors and unfortunately they just did not find the right shape."
Then they saw where Mr. McPhail was from? – a romantic comedy in the House of Care – at the Glasgow Film Festival, and it was when he got involved.
He said his last project was the one that surprised the audience.
"It's a pretty funny and charming movie that has some really serious message and undertones – that's all about kids who are dealing with death and such an age," he said.
"People lean a bit on their hind legs because they do not expect them to cry.
"They laughed and wept, encouraging that it was just this joyous movie – it's just great."
He said he was "blown away" by reaction to film festivals and hoped it could be a big appeal.
"It's not just a movie for kids, or just for fans of horror, or just for music fans," he said.
"We wanted to make a movie that is for everyone to go and enjoy, feeling joyous and feeling good and letting the cinema boom and excitement."
The nomination for Scottish Bafta for the best feature film at the beginning of this year described Mr. McPhail as "awesome".
"It's a zombie music set for Christmas, it's nuts," he said.
The film is also proud of its Scottish roots and location.
"Port Glasgow was perfect for us and people were brilliant," added Mr. McPhail.
"We'll be out in the wind, in the rain and in the snow – no matter what it is, because that's just what we have.
"That's what we shoot, that's what we're working on."
But it was a challenge for actress Ella Hunt, who takes over Anna's role.
"Scotland is a great place to shoot and we had an amazing Scottish crew," she said.
"One of the biggest problems was dealing with the cold because we shot in February 2017, so it was really cool."
However, she said it was the job she wanted to ensure from the very beginning.
"I like crazy concepts – that's more courageous, the better it is in some respects," she said.
"I was really watching the roles of teenage girls who did not have to marginalize teen experience and that was three dimensions.
"Anna is a lot of things all at once, that's the best opportunity, so I'm going crazy immediately."
Roddy Hart and Tommy Reilly, who described the project as "absolutely exciting" from the very beginning, provided the music for the film.
"We have never written a musical instrument before, so trying to get into this style of writing was a whole new universe," said Mr. Reilly.
He described it as "complete freedom of music".
"I think what we loved the most is an ambitious project," Mr. Hart added.
"This is a musical zombie that has comedy elements that are in Scotland, I mean what could be wrong?
"Every time we watch, we find something new with her – it's a magical movie."
The finished film is dedicated to Mr. McHenry – and the man who took the role of the director believes he would like it.
"I can not make films any other, I can not do any other vision, I can only do my own," said Mr. McPhail.
However, thanks to Mr McHenry's friends who have contributed to the film, he believes he has taken a memorial.
"I only know from their reactions that he will be proud and really boasts," he said.
"For someone who was totally prankster and such a funny guy and such a sweet, sweet man, that's a real treat for him."