“I-SPYing on the farm! It can be super – especially if you get the farmer on your side.” By the final edition all the horse-drawn equipment had been replaced by tractors.
 News Chronicle – old fashioned design for the second of the pocket book format series.
 News Chronicle – redesigned cover in the familiar layout.
 News Chronicle – same layout but cover redrawn in colour. 1955.
 Daily Mail / Dickens Press – cover now has series number only. New cover illustration. New content inside. 1962