A Wreath for Rivera by Ngaio Marsh, for the 1949 Club

This is the 15th entry in Marsh’s mystery series featuring detective Roderick Alleyn and his sidekick, Mr. Fox. It starts when Carlisle Wayne, who has been working on Famine Relief in Greece and just returned to England, receives an invitation from her aunt by marriage, Lady Pastern, for a weekend at Eaton Place (wasn’t that where Upstairs Downstairs took place?) in London to be a good influence on her step-cousin, Félicité.

Another cousin, old friend Ned Manx, writes to Carlisle, offering her a ride to London and updates her on the Pasterns’ current estrangement and Félicité’s interest in a very unsuitable musician, Carlos Rivera, from a boogie-woogie band called Breezy Bellairs’ Boys.