When it comes to celebrity best-friendships, Michelle Williams and Busy Philipps reign supreme. Hilarity ensues whenever these two get together, and Williams’ February 7th appearance on Busy Tonight proved no exception.Case in point: Williams regaledthe world with a story of the time she got locked out of a hotel room…in nothing but her underwear.

The actress recalled that she had been staying in a swanky London hotel and was packing (while basically naked) for her return trip to New York the next day. However, things took a turn when she quickly stepped outside her hotel room door to check for a newspaper…and the door locked behind her. She ended up having to ride the elevator down to the lobby in order to get help (the elevator was wall-to-wall mirrors, btw).

Watch Williams tell the full story below.

Williams went on to recall the night she and Philipps met for the first time after Philipps joined the cast of Dawson’s Creek. Williams said the night was “burned in” her brain, and Philipps added that they connected almost immediately.

We seriously can’t get enough of this friendship…or hilarious stories of underwear-clad elevator rides, of course.