So it's no surprise that, when the Hollywood star turned up in the audience of a show at London's Hampton Court Palace, one of the actors fluffed their lines.
Johnny had taken along his two nippers as an Easter Monday treat.
And the family made a beeline for one of the historical plays dotted around the attraction.
But because he didn't make any fuss before his arrival, none of the actors were aware that he was going to be watching.
A source said: "One of the guys performing was so stunned when he caught a glimpse of Johnny that he forgot what he was doing.
"It's not every day that a Hollywood superstar comes to watch you act."
The family then spent the rest of the day visiting the palace and wandering through the maze.
Johnny knows the place pretty well after filming Pirates Of The Caribbean there a couple of years ago.
Girls, he's probably still there trying to find his way out of the maze if you fancy bumping into him.
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