This is the Orion Hardcover Edition of the novella "What Abigail Did That Summer" in Ben Aaronovitch's "Rivers of London" series. It is boldly signed by Mr. Aaronovitch on the title page and dated 19 March 2021. The story is number 5.4 in chronological order of the series.
I'll be listing additional Rivers of London novellas in the series shortly.
Ghost hunter, fox whisperer, troublemaker.
It is the summer of 2013 and Abigail Kamara has been left to her own devices. This might, by those who know her, be considered a mistake. While her cousin, police constable and apprentice wizard Peter Grant, is off in the sticks chasing unicorns Abigail is chasing her own mystery. Teenagers around Hampstead Heath have been going missing but before the police can get fully engaged the teens return home—unharmed but vague about where they’ve been.
Aided only by her new friend Simon, her knowledge that magic is real and a posse of talking foxes that think they’re spies, Abigail must venture into the wilds of Hampstead to discover who is luring the teenagers and more importantly—why?