Watch Ellen punk Michelle Obama while she's signing books at Costco

Former First Lady Michelle Obama has a new book, a memoir of her life's journey getting to the White House called Becoming. To promote it, she went to Costco with Ellen DeGeneres for a signing. But it was no ordinary signing, of course, that wouldn't make for good TV. I don't want to spoil it but let's just say Ellen made the signing more interesting with a bullhorn, a hidden flask, and a case of Preparation H (and more).