Book 48: "What Was Lost" by Catherine O'Flynn

Mickey had been made from a craft kit called 'Sew your own Charlie Chimp the gangster' given to Kate by an auntie. Charlie had languished along with all of Kate's other soft toys throughout most of her childhood, but when she'd started up the detective agency last year she thought he looked the part. Charlie Chimp was no good though. Instead he became Mickey the Monkey. Kate would run through the agenda with him each morning and he always travelled with her in the canvas army surplus bag. The waitress brought the order. Kate ate the burger and perused the first Beano of the new year, while Mickey kept a steady eye on some suspicious teenagers below.

A ten-year-old detective haunts the Green Oaks shopping centre, looking for suspicious behaviour and hoping to foil a bank raid. Twenty years after her mysterious disappearance she seems to be haunting the shopping centre again, when security guard Kurt sees her ghost on the security cameras.

It's funny and sad in turns, and the mystery at the heart of the book is gripping. I'm not surprised that it won the Costa first novel award, as I couldn't put it down until I found out what happened to Kate all those years ago.