I played a White Walker on Game of Thrones

"I was bare-chested, wearing a mini-skirt. We had a zombie army - as you do - and a styrofoam rock for Sam to hide behind."

Ross Mullan is describing his very first scene on the set of Game of Thrones. And when it comes to attention-grabbing entrances in the fantasy show, they don't get more striking than riding out of the mist on a zombie horse, leading the army of the dead past a cowering Sam Tarly.

Over three eventful seasons the Canadian-born, UK-based actor portrayed the most prominent of the fearsome, mysterious White Walkers.

During which time he stole a baby, got stabbed in the back, and was brought back from the dead. All in a fictional sense, of course.

Rider on the storm

Mullan, along with the show's make-up and costume department, brought Game of Thrones viewers their first proper look at an instantly iconic foe.

The White Walker who appears at the end of season two, looks to the camera, and screams? That's Mullan.

The creature who confronts Sam and Gilly in the woods, and is defeated by Sam with a dragonglass blade? That's him too.

Even after this unfortunate on-screen death, Mullan found himself invited back to portray another White Walker, for a scene where he retrieves Craster's baby from the forest, and takes it to The Night's King.

When it comes to some of show's most frightening and talked-about moments, he's been front and centre.

Winter is here: Ross Mullan stepped into the icy shoes of this instantly-iconic nemesis (Photo: HBO/Sky)

Mullan has a particular fondness for his first appearance. One which sent internet forums and the general fandom abuzz.

"It's the reveal. The season finale. All these things came together to unveil the White Walker. He looks down the camera. He lets out that scream. It's spine-chilling."

His most memorable filming sequence, however, came from a particularly challenging shoot for season four.

"I was riding out of a storm made of soap and shredded paper, with my horse bucking beneath me. It was an incredible experience."

Getting the call

Mullan admits he hadn't heard of Game of Thrones when he was originally approached by the show's Oscar-nominated make-up expert Conor O'Sullivan, back in its early days.

The pair had previously worked together on 2010 blockbuster Clash of the Titans, where Mullan - increasingly something of a creature specialist - had played one of that movie's blind witches "under 40 pounds of prosthetics".

"Once you've done one big prosthetics job, and nearly died doing it, they think you can handle anything," he jokes.

Fortunately Game of Thrones proved to be a much more comfortable gig - and Mullan found himself drawn to the combination of mystery and shock value that the White Walker held.

It took five hours of careful application from a team of four people for the White Walker look to be created. But the actor was completely mesmerised.

"When they were putting on the make-up I realised how incredibly beautiful the work was. I was looking at myself in the mirror going, 'wow, this is wild!'"

Creating the character

When he auditioned for the part, Mullan was asked if he could sword-fight (definitely) and ride a horse (definitely not).

Five months of horse-riding training followed, with the rather appropriately named 'Devils Horsemen' stunt team, in order to prepare for the part.

But the really hard work started when the actor stepped onto set.

Ross Mullan brought menace and intensity to the White Walker that stalks Sam (Photo: HBO)

Mullan, who comes from a background in physical and musical threatre, notes there is a particular challenge in bringing a dialogue-free character to life purely through posture and movement.

"You don't have scripts and lines to work with. You try out different things, and are slowly being dictated to visually. It took four or five days to shoot a two-minute scene, because you're seeing how different approaches and variations work."

In the end, Mullan elected to focus on the White Walker's "stillness and intensity", creating a creature that has stealth, presence and purpose.

Mullan's TV and film work has seen him play everything from werewolves to dinosaur librarians, to 'The Silence' in Doctor Who. Kids and parents may also have fond memories of his turn as Nev the bear in CBBC show Bear Behaving Badly.

When the cameras stop rolling

As someone who has previously shot a cosmic horror film in a community centre in King's Lynn (i described his demonic croupier as "truly unnerving"), and a werewolf movie at an industrial unit in Croydon, the surreal way that the every day and the fantasy collide is not lost on Mullan.

"No matter what you're shooting, you have to break for lunch and go to the toilet," he laughs. "It's the little things from the filming process I most remember.

"One of my favourite things about Game of Thrones was coming off set, before I'd taken off the costume, and making small-talk with the make-up crew. You're standing there dressed as a White Walker, and they're going: 'So what are your plans for tonight?'"

#Tbt to that time I came back from the☠to hand a baby to the Night King & I was feeling rock'n'roll #gameofthrones #gotseaso4 #whitewalker pic.twitter.com/OwxalU972h

— Ross Mullan (@rossmullan) August 10, 2017

Mullan, who has been frequently impressed by homemade White Walker costumes worn by fans, now regularly rubs shoulders with Game of Thrones devotees at conventions.

In April, he will attend Thames Con alongside fellow Thrones star Josef Altin (aka Pyp) and Sir Tony Robinson.

Mullan jokes that viewers are often taken aback by his demeanour in real-life.

"I'm very personable. Very smiley and tactile. People are shocked to find I'm not this crazy, ominous, severe and dark character.

"But you need to be easy-going doing a job like that. No one wants someone who's hard work on set."

The joy of practical effects

There seems to be a growing appreciation for practical creature performers in an age of computer generated effects.

Doug Jones, another well-known physical actor, plays a central part as the aquatic monster in Guillermo Del Toro's Oscar frontrunner The Shape Of Water.

Doug Jones (right) alongside Sally Hawkins in The Shape Of Water (Photo: 20th Century Fox)

"I think it has to do with people like Guillermo Del Toro seeing the value in that," says Mullan. "Seeing the difference.

"It's about the difference between 100 per cent CGI work and prosthetic work. The best work lies in marrying the two I think.

"With the White Walkers it's 99 per cent prosthetics. Only the steam coming off my body and the blue eyes are CGI. But you need a bit to blend the scene.

"The BBC use prosthetics all the time for their monsters and they believe there's something more to the characters when there's an actor behind them, bringing them to life."

'I wanted to be a monster when I grew up'

These days Mullan enjoys watching Game of Thrones, but enjoys connecting with the fans even more. "I'm very grateful that I have this in my life. It takes me all over the world," he says.

For the performer, who first started acting at 15, the role and its aftermath has marked "everything I've dreamed of doing in my life".

"To be an iconic character in a TV show? To have toys made of me? It's spectacular."

Ross Mullan in non White Walker mode (Photo: Ross Mullan)

Mullan, who was a TV obsessive as a boy growing up in '70s Canada, recalls the time he fell in love with Scooby Doo at the age of five or six. And in particular, its monsters.

"I told my mother I wanted to be a monster when I grew up. She told me that although I could be an actor when I was older, I couldn't be a monster," he laughs.

"I proved her wrong!"

Ross Mullan is appearing at Thames Con on 28 April, as part of a line-up that includes other celebrity guests from the worlds of sci-fi and fantasy, as well as stunt performances and workshops.

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