Sarah Silverman and beau Michael Sheen enjoy showing off their new romance -- and flying under the radar.

The couple made their first red carpet appearance together in a very public way at this week's swanky Met Gala, but they were also spotted recently having a more private night out, seeing "Sleep No More" at the McKittrick Hotel.

As the show dictates, the comedienne and the actor wore masks during the performance. According to a witness, they seemed to "enjoy" each other's company, holding hands throughout the night.