The idea of alien mind parasites is good if unoriginal, and the two robotic guardian-types are neat but their function in the novel is unclear. The new companion character Fitz remains something of an enigma although he does have some fine moments and some appealing defining characteristics.
There are some interesting concepts in The Taint, but unfortunately the writing never manages to rise above the level of competent and the plot gets a little submerged under a surfeit of characters. It's a pity, especially after the excellence of The Janus Conjunction, Vanderdeken's Children and The Face-Eater. Overall, a disappointing novel. --David J Howe