[In The Wicked One action] is fast, events are credible and consistent given the magical premises, and a dry humour unobtrusively pervades the whole…. Tone and style I found most attractive: apparently casual but always economical; simple but neither patronising nor banal; sympathetic but never sentimental: a good story.
Norman Culpan, "Seven to Eleven: 'The Wicked One'," in The School Librarian, Vol. 26, No. 2, June 1978, p. 42.