An excerpt from Forty Glorious Years: The British Past, American Present, and Uncertain Future of Doctor Who:
The big reveal in the series finale of Doctor Who was not, as anticipated, the introduction of the long-rumored “Terrible Zodin”, but rather the cameos by David Hasslehoff and Sylvester McCoy, establishing for the only time on-screen that the 1996 US series was a continuation of the original and not, as had always been assumed, a reboot. Though not originally intended to end the series, many have in retrospect declared the finale a symbolic “healing” of the rift between the “past” and “present” of the series.
