All episodes Season 1 S01E25 1964-05-09 25 min 1960s BBC

Doctor Who

Sentence of Death (The Keys of Marinus, Part Five)

TV Flash files “Sentence of Death (The Keys of Marinus, Part Five)” as hour 25 of 700 in the TV Flash guide — Doctor Who (1963–) on BBC, season 1, episode 25, aired 1964-05-09, 25 min.

From the desk

How this hour is filed

This leaf is S01E25: listed hour 25 of 700 in the Doctor Who guide, hour 25 of 42 in season 1. It aired 1964-05-09 (25 min). The listed hour before it is “The Snows of Terror (The Keys of Marinus, Part Four)” (S01E24). Next is “The Keys of Marinus (The Keys of Marinus, Part Six)” (S01E26). Broadcast log — titles and dates, not a plot bible.

Doctor Who — Sentence of Death (The Keys of Marinus, Part Five) (S01E25)

Catalog log

Broadcast listing — not a TV Flash recap.

The TARDIS arrives on the planet Marinus on an island of glass surrounded by a sea of acid. The travellers are forced by the elderly Arbitan to retrieve four of the five operating keys to a machine called the Conscience of Marinus, of which he is the keeper. These have been hidden in different locations around the planet to prevent them falling into the hands of the evil Yartek and his Voord warriors, who plan to seize the machine and use its originally benevolent mind-influencing power for their own sinister purposes.

Viewer FAQ

Where does Sentence of Death (The Keys of Marinus, Part Five) sit in the Doctor Who guide?

S01E25 is listed hour 25 of 700 — hour 25 of 42 in season 1, season 1 episode 25.

When did Doctor Who S01E25 air?

Sentence of Death (The Keys of Marinus, Part Five) aired 1964-05-09 and is listed at 25 minutes.

Where should I start with the 1960s serials?

William Hartnell's First Doctor is the origin of the TARDIS-and-companions contract. Patrick Troughton's Second Doctor is the proof that regeneration works. Start at a serial whose surviving episodes interest you; missing-episode gaps are part of the classic-era weather.

In the series

Why this series still plays

A Time Lord, a police box bigger on the inside, and regeneration as infinite franchise life: Doctor Who launched from the BBC in 1963 and never really parked. Early black-and-white serials built the mythology; Hartnell-to-Troughton proved the lead could change without ending the show. The longest experiment in serialized reinvention — woolly, weird, endlessly renewable.

November 23, 1963, is a drop that never really parked. BBC's *Doctor Who* launched a Time Lord and a blue police box bigger on the inside, then treated the lead as renewable inventory. **Regeneration is the window.** Sydney Newman, C. E. Webber, and Donald Wilson were among the early architects. Early black-and-white serials built the mythology; companions, sonic screwdrivers, and cliffhangers became ritual. Rex wants woolly national inheritance. Fine. The business model is recasting without ending the show.

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Also in season 1

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