The Mystery of Ruby's Roulette by Rose Donovan

A secret mission to Lisbon.

A murder at the casino.

And a killer gambling on escape.

New Year's Eve, 1935.

The clink of champagne flutes mingles with the rattle of the roulette ball. Fina’s on a winning streak. But just as she’s about to celebrate, someone gasps, chokes, and slides to the floor. 

The Portuguese police treat it as a crime passionel, but Ruby and Fina have other ideas. Could the murder be linked to the high-level jewel-smuggling operation they’ve been asked to investigate? Working undercover, they scope out the other guests: a handsome airman, an icy princess, a genial mathematician, a suave croupier, and a Brazilian diva with flashy frocks and a personality to match. They all have something to hide – but the truth turns out to be far stranger than Fina could ever have dreamed.

Join Ruby, Fina, Pixley, and Gayatri as they battle with profiteers, saboteurs, assassins, and a ghostly apparition on their twistiest and most captivating adventure yet!