Meet Sister Agnes. She's not your typical nun. She loves killer shoes, sipping prosecco - and solving mysteries . . .

A holy grail . . . or a poisoned chalice?

Agnes has never met Jay Sorrell. But she knows his type. Tall, dark and dangerous to know. A Catholic boy gone bad, he's not one to play by the rules. Now he's vanished, leaving his wife to hunt for him at Agnes's homeless shelter.

But the search ends in tragedy. Late one night, Agnes wakes to the sound of sirens - and the acrid smell of smoke.

St Bruno's church is burning. Agnes races to the scene, in time to see a body being pulled from the smoking ruins. Jay's wife is there too, screaming for her husband.

This was no random John Doe, sleeping rough in the crypt. It was Jay. Whoever lit the fatal match must have known . . .

Down in the ruined crypt, a safe gapes open. Was this the hiding place of the fabled Judas chalice? A priceless family heirloom that's been missing for years.

Agnes won't stop until she lays hands on the treasure - and the truth behind Jay's death.

But once she's sipped from this deadly cup, there's no going back . . .

A gripping, sophisticated crime mystery that will have you intrigued from the first page. Steeped in the intoxicating atmosphere of Central London, from the twisty alleys of Soho to the grimy towpaths of Kings Cross.

This masterfully crafted, character-driven mystery is perfect for fans of Joy Ellis, Robert Galbraith, Val McDermid, L.J. Ross and P.D. James.