Spy Island (Spy Island #1-4)

The world's best spies keep watch over the Bermuda Triangle from a mysterious island outpost teeming with supernatural intrigue, monsters, and evil villains set on global domination. The best of these spies is named Nora Freud (no relation). She knows eighty-seven ways to kill someone with a cocktail toothpick, and she's used thirty-two of them. Lately though, Nora has started to feel like she's going through the motions. Close the temporal portal. Assassinate the genocidal maniac. Have sex with the MI-6 agent. Plus, the island has gotten kind of touristy. She agrees to one last mission. But when Nora's troubled marine cryptozoologist sister shows up unexpectedly, warning of mermaid attacks, Nora realizes that boredom is not her biggest problem.

Collects Spy Island (2020) #1-4.