Elf: Our sweep is complete, sir. We've been over every square meter of this ship and there's nobody home.
Elf: There are unfinished meals, and infrared traces on some of the furniture. Whoever used to be here hasn't been gone very long.
Schlock: Oooh! Did you check the air vents?
Elf: Nobody who has seen you in action fails to check air vents, Sergeant.
Schlock: . . . 'cause that's right where I'd be.