T.S. Eliot’s collection of poems entitled Old Possum’s Book of Practical Cats is best known today as the basis for the mega-hit musical Cats. The poems were originally written for his godchildren, whimsically inventing a society and psychology for the feline species. Although written over the course of the 1930s, the copyright clock did not begin ticking until they were published – with illustrations by Eliot – in 1939, and would have entered the Public Domain in 1996. The illustrations by Nicolas Bentley in the 1940 edition would have become public property a year later.
For good or ill, the songs and staging of the musical would be unaffected if the source material were in the Public Domain. Likewise, the illustrations that accompanied later editions, such as those by Edward Gorey (1982) and Axel Scheffler (2009) would still be safely under copyright.