You should pack a 'change of underwear'. [=additional underwear that you can wear at another time]
He answered the door 'in his underwear'. [=while wearing only underwear]
(..) - Mm-hmm. All right, that settles it, then. - Okay. - We're on, all right. Oh, wear your best dress. Leave those underwear at home. Kruller, looking good. Hello, Hank. - Where's Baldo? - He's in the guest room. Say hello to Love. (..)2014 TvShow: Californication Title: Grace Season: 7 Episode 12