Corpse Marker appears to suffer from the old case of unnecessary sequel to a beloved classic. However, I can't be too hard on it in some regards due to what eventually became of this intermittent story between The Robots of Death and spawning the truly excellent Occam's Razor of the Kaldor City range, I only really decided to read this due to the fact some of the characters of the book appear in the third story of the range, Hidden Persuaders.

The Doctor and Leela arrive on the planet Kaldor, where they find a society dependent on benign and obedient robots. But they have faced these robots before, on a huge Sandminer in the Kaldor desert, and know they are not always harmless servants. The only other people who know the truth are the three survivors from that Sandminer — and now they are being picked off one by one. The twisted genius behind that massacre is dead, but someone is developing a new, deadlier breed of robots. This time, unless the Doctor and Leela can stop them, they really will destroy the world.

Once again, Chris Boucher establishes that Blake's 7 is indeed part of the Doctor Who universe with a prominent appearance from Psychostrategist Carnell, see Season 2 Episode 3 - Weapon, and while not a fan of Blake's 7 myself due to being spoilt by the Gerry Anderson productions of Space: 1999 and UFO respectfully doing the concepts better and far more interestingly, I can appreciate the attempt at continuity here. The plot is pretty decent but I think what holds it back is how Chris handles a lot of his side characters and genuinely just writes them as cannon fodder rather than three dimensional people, although I can appreciate him trying to up the antie of The Robots of Death, however in the process he lost what made The Robots of Death so loved, the tight and claustrophobic atmosphere is gone in favour of a city wide threat. The Doctor and Leela are great, but I don't remember much about the others; they were very disposable in all honesty.

Overall, not the worst story I've read, but it doesn't do a whole lot that warrants a revisit, however, it did give us the magnificence that is the Kaldor City range, so I can cut it some slack there…