He says he felt "very safe and comfortable" during a stunt near the end of "Get Smart."
It's the fight scene where he's on a railroad track going 50 or 60 miles an hour.
He agrees "it was challenging."
But, he says the stunt coordinator knew what he was doing.
Besides, Johnson says he was harnessed into the SUV in the scene.
And, he says "if you're into stunts and physicality like that as an actor, you look for days like that."
