1929: Miss Clara Vale is a woman ahead of her time. Rather than attending Oxford to bag an eligible Duke (as her mother, Lady Vale, so desperately hoped), she threw herself into a degree in chemistry, with aspirations to become a scientist in her own right. But the world isn't ready for Clara. Unable to land a job in science because she's a woman, she is stuck behind the desk at a dingy London library. Until her estranged Uncle dies suddenly, leaving her his private detective agency, and laboratory, in his will.

As Paris rediscovers its joie de vivre, Tabitha Knight, recently arrived from Detroit for an extended stay with her French grandfather, is on her own journey of discovery. Thanks to her neighbor and friend Julia Child, another ex-pat who's fallen head over heels for Paris, Tabitha is learning how to cook for her Grandpere and Oncle Rafe and Tabitha's sojourn is proving thoroughly delightful. That is, until the cold December day they return to Julia's building and learn that a body has been found in the cellar.

Northern Ireland, spring 1981. Hunger strikes, riots, power cuts, a homophobic serial killer with a penchant for opera, and a young woman’s suicide that may yet turn out to be murder: on the surface, the events are unconnected, but then things—and people—aren’t always what they seem. Detective Sergeant Duffy is the man tasked with trying to get to the bottom of it all. It’s no easy job—especially when it turns out that one of the victims was involved in the IRA but was last seen discussing business with someone from the loyalist Ulster Volunteer Force.

June 1933. Independent, young Kitty Underhay has been left in charge of her family’s hotel, The Dolphin, on the tranquil English coast. But when several rooms are broken into and searched, including Kitty’s own, she quickly realizes that something out of the ordinary is afoot at the hotel. Soon, rumors are flying in the cozy town that someone is on the hunt for a stolen ruby. A ruby that Kitty’s mother may well have possessed when she herself went missing during the Great War.

Nestled high in the Tuscan hills lies Villa Volpone, home to renowned crime writer Jonah Moore and his creative writing course. It’s also the last place retired DCI Dan Armstrong expected to spend his retirement! Dan’s no writer, but maybe this break will help him to think about the next chapter in his own life story? But only days into the course, Jonah Moore is found stabbed to death with his award-winning silver dagger! And Dan finds himself pulled out of retirement with a killer to catch.