Doctor Who: The Stolen Earth

Quotes

 * Captain Jack Harkness: Martha, back at UNIT, what, what did they give you? What was that key thing?
 * Martha Jones: The Osterhagen Key.
 * Harriet Jones: That key is not to be used, Doctor Jones. Not under any circumstances.
 * Captain Jack Harkness: But what is an Osterhagen Key?
 * Harriet Jones: Forget about the key, and that's an order! All we need is the Doctor.