The duo is usually discreet about their relationship, however, photographs of the actor and 'Coldplay' lead singer spending time together surfaced on Monday.
Johnson, who is best known for starring in the 'Fifty Shades' film franchise, said: "The thing is, people are not behaving normally. If you go to a party, you f****** rage."
Singing in front of people is actually so terrifying for me. And we had to shoot the scene where you don't even really see me. The camera's in the back of... you can't even really tell what's going on, and I was meant to be performing in community theatre.