Rivers of London: The Fey and the Furious #4 (Titan, 2020)

Trouble is never far from Peter Grant, even when he's off-duty. After suspiciously a suspiciously supernatural cargo washed up on the Netherlands' shores in the back of a boy racer's car, Peter infiltrated illegal street races organised by criminal mastermind Emmanuel Cross. His investigation swiftly took a wrong turn as he once again found himself speeding into Fairy Land. Although Peter has uncovered the mysterious cargo's source with Cross' cronies slaughtering unicorns for their horns, he is trapped in this magical realm. To make matters worse, the Fairy Queen has found him and is ready to resolve their unfinished business...