This serial also marks a shift in strategy for the evil pepperpots, who emerge from using the blunt instrument of superior power seen most clearly in The Dalek Invasion of Earth, opting instead for Machiavellian plotting and subterfuge. This time it is in the distant year 4000 and the Dalek's have once again turned their attention to our solar system. Rather than attack outright, as they did 1900 years before, they strike up a conspiracy with the humans' highest authority, Mavic Chen the Guardian of the Solar System. He alone has access to the rarest mineral in the universe, taranium, which is needed by the Daleks for their Time Destructor.
The Doctor and his companions Steven and Katarina, newly acquired from ancient Troy, become embroiled in the master plan when they land on the planet Kembel. From there they take off by shuttle to the prison planet Desperous, go from there to Earth, get molecularly disseminated to the planet Mira with its invisible wildlife, are brought back to Kembel and escape in the TARDIS to Earth in the 1960's, 1920's and ancient Egypt respectively. Finally they return to Kembel to thwart the Daleks' plan once and for all.
This serial features many unique twists that set it apart. The Daleks, for instance, are not the only villains to return. Who should afflict the Doctor in the Land of the Pharaohs but the Monk? The bumbling Time Lord has tracked down the Doctor to enact his revenge, but quickly finds himself out of his element when he gets mixed up with the Daleks. It's really a shame that the conniving Monk, played by Peter Butterworth, has yet to return to the Doctor Who canon. After being left in the cold by the Doctor's counterplot, he would never return. If the Master could survive the Time War, why not his more hapless, comic predecessor?
There is also the infamous "breaking the fourth wall" segment of the largely disposable middle episode, a Christmas special, in which William Hartnell toasts a Happy Holidays "you at home." This shattering of the suspension of disbelief was a regular policy for the BBC of the time period, which involved characters turning to the camera and wishing everyone a Merry Christmas from the cast and crew.
Most notable was the extermination of no less than two of the Doctor's companions: Katarina and Sara Kingdom. Katarina suffers death by being taken hostage by a stowaway from the prison planet in an airlock. Whether by accident or design, she opens the door and blasts both of them into space. This loss is especially unfortunate, as Katarina had some of the greatest potential of any companion. Where Vicki was able to contrast the companions of the present day to one from the future, Katarina was able to do so to one from the ancient past. This is a marked improvement over the most recent Doctor's companions all being from modern England. Unfortunately, the producers felt the other way and, not wishing to explore the possibilities, got rid of her fairly early on.
Kingdom, who came and went with this serial, met her horrifying end in the climax as a victim of the Time Destructor. Contrary to Katarina, her role was fairly ambivalent. The TARDIS crew met her when she, as a space security agent, executed her rogue brother Bret Vyon. After learning about Mavic Chen's involvement, Vyon assisted The Doctor, only to suffer the consequences. His appearance is particularly noteworthy for having been the first role for the late Nicholas Courtney, who would go on to become one of the best-known character in series history, Brigadier Alistair Gordon Lethbridge-Stewart.
The length and status of The Daleks' Master Plan echoes the first Doctor's other great, lost epic, Marco Polo. Both are sprawling adventures ranging across Time, Space and the Silk Road - the former a Science Fiction story and the latter an historical - and both have perhaps inflated somewhat in reputation because of their absence. This serial is certainly a welcome change from the comedy of The Chase, but the new direction for The Daleks takes some getting used to after the frightful brutality of The Daleks and The Dalek Invasion of Earth. It is also the last appearance of the Daleks in the first Doctor's run.
After foiling the Dalek plot, as they are wont to do, the Doctor and Steven move on to 16th century France. Though Sara Kingdom died, her story is not yet complete. Big Finish has continued her saga in the Companion Chronicles audio series.