(No, I have not missed a book — got my numbering wrong last month, with two numbered 69, and have now corrected.)
Abridged on 2 CDs and read by Anthony Head. This has a slightly complicated pedigree — it’s the abridged audiobook of one of a series of novels about amateur sleuth and crime novelist Paul Temple, which themselves are novelisations of a long-running series of radio plays. The book was published in 1971, but the radio play was first broadcast in 1948-9, and the book has a strong period feel. Great fun.