Spy: Bret McKenzie takes Johnny Depp out for Milk

Johnny Depp. Photo / Getty Image

Bret McKenzie is giving friend Taika Waititi a run for his money on working with Hollywood big-shots.

Waititi will next year direct Thor 3 with Australian actor Chris Hemsworth in Australia.

McKenzie has written a script for a movie adaptation of Neil Gaiman's hit 2013 children's book, Fortunately, the Milk.

Depp - one of Spy's all-time favourite Hollywood A-listers - has signed on to act and produce the film. It is understood Hollywood movie-making titan Fox is considering a pitch to take up rights for the production.

The movie's premise could be Peter Pan meets Jumanji. Gaiman's book is about a dad left alone with the kids who nips out to buy some milk and ends up being caught up in a fantasy adventure involving aliens, dinosaurs and time travel.

Such a colourful storyline could be a perfect role for McKenzie's Flight of the Conchords' co-star Jemaine Clement.

McKenzie is hot property in Tinseltown since winning an Academy Award in 2012 for his track Man or Muppet, which featured in The Muppets movie.

And we all know that almost every movie Depp stars in seems to turn to gold, including The Pirates of the Caribbean series, Edward Scissorhands, Once Upon a Time in Mexico, The Tourist and Fear and Loathing in Las Vegas.

In February, Depp married American actress Amber Heard, whose film credits include Friday Night Lights, Pineapple Express and The Rum Diary, which also starred Depp.

In August, Clement confirmed he and McKenzie had started working on a potential movie adaptation of the Flight of the Conchords series.

Rumours of a movie based on the comic band have existed since Clement and McKenzie called time on the award-winning HBO TV show.

"We have started writing," Clement said. "But who knows if it will ever be made. We've written some notes for some different film ideas. We're not down to the stage where we're going, 'The film is going to be like this'."