10 Doctor Who Endings Nobody Saw Coming
2. The Caves Of Androzani - Part Four
At the end of the 1984 serial The Caves of Androzani, the Fifth Doctor succumbs to an illness caused by a toxin. After hallucinating the faces of his past companions, the Doctor regenerates into a new form, swapping out the visage of Peter Davison for that of Colin Baker.
It wasn't just the character's appearance that had changed. Something was different about this new Doctor, and something felt a little... off.
His first line in the role - "You were expecting someone else?" - was delivered with a biting sarcasm that felt very out of place with the bubbly, eccentric Doctors of old.
This harsher portrayal of the character lasted less than three years, but the initial introduction of this more serious version of the Doctor is something that fans are still grappling with to this day.