The Kramer vs. Kramer star hired Sheridan to star in his directorial debut Quartet alongside Dame Maggie Smith and Tom Courtenay, and jetted from the U.S. to London to see her perform in a play.
Hoffman kept his visit a secret, booking tickets under a different name, and Smith admits she wept after hearing the acting legend was waiting in her dressing room.
She tells the London Evening Standard, "I was so starstruck when I met him. I was just in a play recently and he flew over to see it but he didn't tell me because he knew how nervous I get.
"So he booked the tickets under a different name and then afterwards I got a phone call to my dressing room saying 'There's a Mr Hoffman to see you', and as soon as I saw him again I started crying. So as soon as he sees me now he says 'Don't cry!'
"What an honour to be asked to work with the acting royalty that's in the film (Quartet). Going to work every day was a masterclass. I had to pinch myself really that I was on screen with those people."