Diana Bakewell and Zaf Williams are cementing their reputations as London's best tour guides. They've also learned that they're not bad at solving mysteries. 

But when Kamran Dadashov, the father of Zaf's new boyfriend, hires them for a tour, they know they need to pull out all the stops.

The group consists of three wealthy men, old friends and occasional rivals. They aren't just seeing London's sights: there's a challenge, involving a race, postcards, and an egg sandwich. But when they begin their tour on the London Eye, Diana looks down to see a man fall from a boat belonging to one of the group.

The police arrive and can't find a body. Diana is accused of fabricating the whole thing. But then when a body washes up further along the Thames, she knows she's got another murder on her hands.

Can Diana and Zaf solve the mystery before the killer strikes again? And will Zaf be able to juggle his relationship and his work?

Find out in Death on the Thames, the fourth book in the London Cosy Mysteries series. Perfect for fans of Richard Osman, Anthony Horowitz, and MC Beaton.