The Reign of Terror is the finale to Season 1 of Gnoctor Blu. It's pretty strong, and unlike the proceeding story, uses political intrigue as the primary impetus behind the plot, instead of tacking it on in half-assed way to meet length requirements.
The entire story exists, but it inexplicably becomes an anime during two episodes.
The crew arrives in late sixteenth-century Paris where they're accidentally mistaken for terrorists by other terrorists. Of course, they get split up, because apparently there is no other way to write historicals. Anyway, the Doctor gets left for dead, while everyone else is taken to Paris as guests of Madame Guillotine. Of course, they aren't executed and meet back up with the Doctor, while Robespierre gets shot in the mouth and Susan gets vewwy sick. It's been like 2 years since I've seen this, so I'm missing some details, but watch it. The ending speech by Hartnell is very pensive, considering the future the show will come to have and the fact that he's so unaware of it. God, HE DIDN'T WANT TO GO.
The Doctor fulfills his season long wish of cracking a man's skull with rocks in "Guests of Madame Guillotine".