The Radio Times issue for 28 August 1975 covered the story with a feature on Loch Ness by Anthony Haden-Guest with artwork from Frank Bellamy. You can read more on the Radio Times story guide by Mark Braxton.
What is Nessie? Who can tell? In a new series starting this week, Dr Who takes on the unidentified incumbent of Loch Ness. Here Anthony Haden-Guest plumbs the murky depths of the Scottish mystery.
In article about Doctor Who in The Listener for 2nd October 1975, Jack Waterman wrote:
On another level, admirers of polystyrene suitings—to say nothing of shareholders in plastics firms—must like the work to be seen on Dr Who. To name but one monster, and the most recent, the Zygon was a creation of genius—an amber-coloured, heavy-duty plastic individual—and yet another tribute to designers who have, through this programme alone, over the years put the BBC well ahead, in a field whose first drawing-board effort was no less than Frankenstein's creation. [p. 437]