Allan collaborated with many well-known British comic strip artists, including Jim Baikie and Arthur Ranson.
Following a period of national service in the Gordon Highlanders from November 1954 to November 1956, having been on active service in Cyprus, Allan returned to Amalgamated Press and after working on Super Detective Library, eventually became co-editor of what was now known as "Cowboy Picture Library", with Alan Fennell.
Eventually, he was recruited to join the team producing Marty, the first photo-strip teenage romance weekly published by Newnes and Pearson.
Later, he was heavily involved with Alan Fennell's Century 21 Publishing company, becoming associated with Gerry Anderson classics such as Stingray, Thunderbirds, etc.
He was also the mainstay scriptwriter for Fennell's Look-In magazine, and at one time was writing every strip in the paper, including DangerMouse.