The Doctor (William Hartnell) and his companions, Ian (William Russell), Vicki (Maureen O'Brien) and Barbara (Jacqueline Hill), finally escape the Space Museum, only to discover that the fiendish Daleks have mastered time travel. The TARDIS voyages from distant worlds to the Empire State Building in the ensuing chase. Just when the travelers think they're in the clear, a robot army in the future arrives to imprison them.