| The first incarnation of the Doctor
was portrayed by William Hartnell. During Hartnell's tenure, the
episodes were a mixture of stories set on Earth of the future with
extraterrestrial influence, on alien planets, and in historical events
without extraterrestrial influence, such as Marco Polo, one of the lost
serials. In his last story, The Tenth Planet, the Doctor gradually grew
weaker to the point of collapsing at the end of the fourth episode,
leading to his regeneration. |
