You are dealing with a professional. Probably a hired killer. Resourceful, highly intelligent. A computer specialist.

Kaldor City is perhaps the lesser-known series from the relatively small Magic Bullet Productions, emerging from the shadow of its bigger brother, Big Finish, with its groundbreaking series The True History of Faction Paradox. But by god, do they have me by the balls, and it's only the first story! I've never heard such a fantastic start to a series in all my life, and if anything, if they keep up this level of quality, this might end up as my favourite Doctor Who spin-off ever... and that's saying a lot.

Kaldor: A city of robots on a world of robots. The Board runs the Company, and the Company runs the planet. Nothing happens in Kaldor City without the Board's approval. So, how come its members are dying? Company Chairholder Uvanov is faced with an escalating problem: political allies and enemies are being killed, and nobody knows who will be next or why. Even Carnell, the ex-Federation psycho-strategist, is at a loss to provide an explanation. One man may hold the answers-- a man who crossed the border into Kaldor City six hours ago: Kaston Iago, a man with a past and maybe an agenda. A man with the skills to set everything right.

Magic Bullet Productions came into existence when Alan Stevens had the idea for an audio series loosely based on the film Yojimbo by Akira Kurosawa. The film is about a Samurai who plays two powerful families off against one another in order to benefit himself. The film very loosely inspires Kaldor City, but the ties to the more real-world influences in its writing help to dissociate it from Kurosawa's original work.

Like its origins, Occam's Razor is very much a murder mystery but unlike The Robots of Death, Occam's Razor's roots are very much steeped in real-world history, with the patented Doctor Who twists, however, unlike its parent show, Kaldor City hardly skimps on its mature storytelling. The events of the story are based on the Night of the Long Knives, where the SS, under the authority of Adolf Hitler, purged the Nazi paramilitary organisation called the Sturmabteilung (SA), hundreds were killed. A clue to the source material appears in the name of the hotel Iago stays in called Kolibri, which is German for "Hummingbird", the codeword used to send the execution squads into action on the day of the purge. The fact that Kaldor society is very clearly inspired by Nazi Germany only heightens the rather horrific reality of our character's situations.

Brilliantly acted, fantastically written and highly recommended, Occam's Razor is a near-perfect start to what might end up being Doctor Who's best spin-off. Although I would have probably gotten even more out of this story if I had read Corpse Maker or seen the finale of Blake 7, even without those, Occam's Razor is utterly fantastic and well worth your time.

A pentagram... and it's red. Red attracts psychopaths.