Black Widow (The Beatrice Stubbs Series, Band 9)

Beware the Female of the Species
Private Investigator Beatrice Stubbs is bored of hanging around supermarkets, trying to prove infidelity or petty fraud. She yearns for a job with excitement, adventure and some continental travel. Lesson: be careful what you wish for.
Enter one unexpected assistant, two commissions and her life spins from dull to deadly. While hunting an assassin in Budapest, gossamer traces lead to a respectable family business in France. Despite undercover infiltration of a Parisian perfumery and Bordeaux vineyard, her enquiries soon hit an impenetrable wall.
When the scale of the network emerges, Beatrice still thinks like a cop. She calls in a favour and burns her last bridge, leaving her with nowhere else to turn. Now, she and her assistant are defenceless against predators with many eyes.
The web contracts, trapping them like insects. Entangled in the enemy's lair, her back against the wall, she can only pray she has not run out of friends.
"I'm a loose end. They don't like loose ends."