Inhabiting the role of a living, breathing and talking rabbit is no mean feat, as Watership Down's James McAvoy has revealed he almost passed from the strain of creating his spirited animal sounds for his character Hazel.

The Split actor plays the main protagonist in the BBC and Netflix adaptation of the much-loved Richard Adams novel, which also stars Peter Capaldi, Olivia Colman, John Boyega, Gemma Arterton, Ben Kingsley and Nicholas Hoult, to name but a few.

Watership Down stars James McAvoy and Nicholas Houltpinterest
Getty Images

Recalling what the recording process was like - each actor recorded their parts separately and without seeing any of the animation - McAvoy told press including Good Housekeeping at the show's recent screening: "You find yourself getting really lightheaded doing the rabbit noises…

"I almost passed out a couple of times doing those sounds!"

Gemma Arterton BBC One's 'Watership Down' Photocallpinterest
Mike Marsland//Getty Images

Arterton - who plays Clover in the drama - revealed that the majority of the cast decided to use their own accents to play their roles, giving the series a contemporary feel, and that they recorded the animal sounds at the end in case they damaged their vocal cords.

"When you record [parts which read] 'you're running away from a cat now' and 'you’re sniffing the air'] you just have to be a child really, it's quite fun.

Watership Down rabbits BBC/Netflixpinterest
BBC

"It was funny because you do have to record it at the end or you might hurt your voice, but it's actually liberating. You have to let yourself become a complete idiot."

"I had to nibble on a couple of pencils in the recording studio!" Hoult admitted. See below...

Nicholas Hoult in Watership Down pinterest
BBC

Meanwhile, Hoult also revealed the unusual way he secured his part as Fiver in the series. Fiver is Hazel's younger brother, and his trippy premonitions prompt the band of rabbits to flee their warren.

"James was wearing a Watership Down t-shirt when we were filming in Montreal together and I was like, oh Watership Down, and James was like, 'yeah, I'm doing the voice for it'.

"And I was like, 'really they’re doing another one?' and you were like, yeah, you should do it, and that’s how i got on to it."

Executive producer Rory Aitken said that they were flooded with calls from actors desperate for a part no matter how small, saying: "The calls became incoming from actors saying, 'we want to do it'.

"And even at the very beginning of episode one small part is played by Taron Egerton, who rang our casting director and said, 'I just want to be in Watership Down, I don't care what it is, I'll come and do it'.

"Everyone went the extra mile for this project because they all how special the story is and the subject matter."

The classic story follows Hazel, Fiver, and their fellow band of Sandleford rabbits as they escape the destruction of their warren and fight for survival on their quest to find a safe themselves a safe place to make a home. John Boyega stars as Bigwig, and Daniel Kaluuya plays Bluebell.

preview for Watership Down Trailer

Watership Down will air on BBC One on Saturday 22 December, and Sunday 23December.

Netflix will release Watership Down in four parts on 23 December.