The clue is in the title. Codeword meets double acrostic in a dastardly puzzle for dedicated codeword fans only. The puzzle consists of two main grids. The first is a codeword containing every letter of the alphabet at least once, coded with a number from 1 to 26. But there's more… the two outer columns of this first grid contain the name of an author and the title of one of their works. The letters in these columns are coded with new numbers from 27 onwards.
A second grid contains a quotation from the work featured in the first grid. In this quotation grid, the letters are coded with the numbers from 27 onwards. Not all letters of the alphabet will necessarily appear in this second set that codes the author, title and quotation.
For each code, solvers are given a reference grid to note decoded letters and an alphabet to cross off letters as they identify them.
Each part of the puzzle helps with the solving of the rest. Initially solvers concentrate on the main codeword part of the first grid. Intersecting letters on the Across words of this grid begin to suggest names and words for the author and title in the two outer columns, revealing part of the second code. These letters can then be transferred to the quotation grid, which in turn will give more clues to unidentified letters in the names of the author and work. The puzzle is completed by moving between one grid and the other.
It's fiendishly clever on the part of the setter and undoubtedly a favourite of the code-cracking cognoscenti. Just don't expect to rattle it off in your coffee break.