Review of all 6 episodes:
This story starts really well with an intriguing and gritty opening episode and although it fades a little bit by the end it is still overall very good.
The story involves The Master having a mind controlling machine which extracts evil from criminals. It also features a prison take-over, a world peace conference and an attempt to steal a powerful missile. Some of these elements are slightly muddled padding to fill out the 6 parts. Following on from a tight four-parter it is probable that if this one was similarly pared down it would be nearer to top Doctor Who standards rather than just a good medium quality one. Instead, in order to pad things out there is a rather complex and not fully credible plot. The plan hatched by The Master is a bit too convoluted and too reliant on everything going exactly to plan and schedule. As a result it is seen by some as too unlikely as a plot. However, the good qualities of acting, characterisation, action, scary 'monster' (the Keller Machine) and political intrigue all go towards glossing over the relatively small concerns over the plot.
The Master (Roger Delgado) makes for a superb adversary again despite his occasional indecisive ways and Mailer (William Marlowe) is a well acted and convincing henchman. Jo Grant (Katy Manning) is a stronger character in this than in Terror of the Autons (her first story) and this establishes her much better. The Brigadier (Nicholas Courtney) and UNIT are good additional support as ever and there is a gritty prison setting plus exciting military and political elements. I am not a fan of the music and sounds created by Dudley Sutton but accept that at the time they were fresh and innovative and while the incessant noise of the prison riot is very annoying it is more realistic than a quiet riot!
This is a very enjoyable serial; action packed, interesting and well produced. It could have been better but is still a solid adventure.
Episode ratings: Episode 1 - 9, Episodes 2 & 4 - 8.5/10, Episodes 3, 5 & 6 - 8/10 = 50/60
Overall: 8.33/10
