Liam Neeson wore 'a onesie with ping-pong balls attached' to film motion-capture 'Monster' role

NEW YORK, Dec. 26 (UPI) -- Liam Neeson -- who is known for his tough-guy roles -- admits he felt "totally ridiculous" as he portrayed via motion-capture and animation the enormous, terrifying-looking creature at the heart of J.A. Bayona's A Monster Calls.

The contemporary, live-action movie is based on the young-adult novel by Patrick Ness. It is about the Monster's visits to a young teen [played by Lewis MacDougall] whose mother [played by Felicity Jones] is dying.

Asked by UPI at a recent round-table interview with reporters in New York about the physical transformation he underwent and how that impacted his performance, the Northern Ireland-born star said he was first shown a bust of the character, then encouraged to pretend he was 40 feet tall, while his every movement was documented by 70 cameras.

"And you're in the middle. And you're in a onesie with ping-pong balls attached to you," the 64-year-old actor revealed. "It's totally ridiculous. And they're all connected to sensors and the computer nerds are giving you digital makeup is what I would call it. And you're acting away."

Although movie magic makes it look like MacDougall's character is on-screen with Neeson, he wasn't actually in the room when Neeson was recording his part.

"I was acting to a puppet or little doll to get the scale and perspective right, so that was interesting," the elder actor confessed.

As for getting the Monster's voice right, Neeson said he studied carefully the facial features of the statue he was given.

"And that informed me a lot because it looked like someone had just squashed their face up against a tree," he reasoned. "And I thought, 'Well, his nose is broken, so that affects breathing and that'll affect the voice in some way.' And just those little things. ... It's a lovely film, isn't it? ... It's very entertaining and emotional. And it's like the book. It's just I remember it was a very, very quick read. But it kept coming up and biting me in the back of the head again. I'd keep reaching for it, you know, there's a wonderful essence on it."

Co-starring Sigourney Weaver and Toby Kebbell, A Monster Calls is in theaters now.