It's difficult to read Luke Jennings's Codename Villanelle without imagining the Killing Eve TV series (see trailer below), but here goes.
The book opens in an Italian lakeside villa where a group of twelve men are meeting to discuss their European business interests, which are being threatened by a Sicilian mafia boss. The men unanimously decide he must be killed. We then meet the assassin Villanelle and her handler Konstantin.
The story follows Villanelle as she carries out assassinations on behalf of the shady group of twelve, taking in Paris, London, Beijing, Russia and elsewhere. Villanelle is a psychopathic killer who enjoys a "Grey Goose vodka Martini," "her feet in her strappy satin Louboutins," and wearing a "Miu-miu sweater". There's a lot of named merchandise in the story. By contrast, Eve the British agent on Villanelle's trail, is a more nuanced character who becomes obsessed with finding the female assassin, to the point of harming her marriage.
It's a fast-paced plot, written primarily in the present tense, which gives the impression that one's reading a screenplay. Some may find that this places them within the action, but it can also promote a sense of detachment, which is not necessarily a bad thing, especially when it's used to reflect Villanelle's thoughts and actions. It also serves to focus Eve's tension in a particularly enjoyable scene where she and her colleague have broken into a house.
There's no resolution at the end of the book. Some may find this a clever way to encourage readers to buy the next instalment. Others such as myself consider it an annoying ploy.