New York - one of the greatest cities on 21st century Earth... But what's going on in the Museum? And is that really a Woolly Mammoth rampaging down Broadway? An ordinary day becomes a time of terror, as the Doctor and Amy meet a new and deadly enemy. The vicious Army of the Vykoid are armed to the teeth and determined to enslave the human race. Even though they're only seven centimetres high. With the Vykoid army swarming across Manhattan and sealing it from the world with a powerful alien force field, Amy has just 24 hours to find the Doctor and save the city. .