Creating iconic villainous opponents for our Doctor to confront with the (temporary) loss of the Daleks proved difficult in the late sixties, but there were occasional creative/design triumph successors, most notably with the Ice Warriors conceived by Brian Hayles, who, after their intriguing debut story, would return for another battle with Patrick Troughton in a more action-packed adventure that saw the cold beings plan to conquer Earth via humanity's use of a unique Transmit system. The end result, The Seeds of Death, was another viewing success in a season that was a mixed bag of fortunes, and which would see the warriors of Mars, and their expensive to make costumes, eventually return to the show during the colourful Pertwee era...
Great cover art for the excellent fan made An Adventure in Time and Space partwork series of the mid-eighties, by Stuart Glazebrook.
The never dull Target novel adaptation by Terrance Dicks makes a fine conversion to BBC Audio Books, read by none other than the versatile David Troughton himself.
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