Ruby Rose can't use any of the sign language she learnt for John Wick: Chapter 2 in real life as it's too threatening.

The Australian actress stars in the new movie as a mute assassin named Ares, who acts as a security enforcer for Santino D'Antonio, a deadly killer played by Riccardo Scamarcio.

For the film, which features Keanu Reeves in the title role, Ruby was required to learn how to communicate via sign language, but she admits the skill hasn't proved too beneficial in her everyday life as she only recalls very specific, and often violent, signals.

"The problem is that I only learnt words that I can't have conversations in," she said during an appearance on Late Night with Seth Meyers on Wednesday (08Feb17). "Unless I want to say, 'Hi, how are you? Would you like to die now or later?' and 'Run for your life, now quickly,' or 'I'm going to get you' - they're not things that you actually want to say to people.

However, Ruby is grateful that the project allowed her to learn a new ability, and she's hopeful more people will soon take up signing.

"I was so excited to learn it. I think that it is a beautiful language and I actually wish that everyone could speak it because it is a very universal language," she shared.

Meanwhile, the 30-year-old also revealed that she's conjuring up another alias to use when checking into hotels and meeting drivers at airports, as fans figured out she went by the name of Tommy Pickles when she was traveling. Ruby realized she'd have to drop the name, inspired by one of the characters in Nickelodeon TV series Rugrats, when people started openly messaging her about it via social media.

"I had successfully had Tommy Pickles for a year and a half and nobody knew that I was Tommy Pickles... And then people worked it out and they would tweet, 'Don't worry I won't tell anyone, but I know you're Tommy Pickles,'" she laughed. "But I was like, 'You just told everybody because you just tweeted it.' So now they know so I have to change it. I have to think of something good though, how do you beat Tommy Pickles?"