The scene:
A few years back, a prominent and fan-beloved older VO actress was recording lines for a game I was working on. On the way out of the studio, a pair of underpants (!) fell out of her pants leg in the parking lot. She walked on, oblivious, while my friend, the VO director, battled between the urge to be a good Boy Scout and call her back, or pretend the mounded heap of panties on the asphalt had never happened.
Boy Scout won; he called after her and handed her the undergarment, simply saying, "Miss X, you dropped this." She took one look, then grasped his wrist and said the line -delightedly - I will never fail to use in these mortifying situations: "Oh, we're SUCH good friends now!"
My VO director approached me, as one of 4 women on the game, and obviously the wisest, to ask how the HECK does a woman lose her panties down her pants leg?!

My hypotheses:
- She took off both pants and underdrawers in the loo, but somehow neglected to put the panties on.
- it was a thong and the elastic gave. (Note: traumatized VO director, squirming at idea of beloved older icon in thongs, affirms that the item was not a thong, so I'll say he would know and invalidate this guess.)
- The last time she wore those pants, she took off both pants and underwear at once but neglected to pull out the unders. These lodged comfortably inside a pants leg until the next time she put them on, whereupon they wriggled ever lower until they finally exited via the cuff of her pants and viola.
- Similar to above, a clean pair of panties static-clung to the inside of her pants in the drier until she wore them and alas, the static could finally cling no more.

That's all I have. Can YOU solve the mystery of The Falling Underpants??