Lost city - Clive Cussler (Numa files #5)

Goodreads 3.94

This is Kurt Austin's toughest assignment yet ...The discovery of a body frozen for ninety years in a glacier high in the French Alps seems of unlikely concern to Kurt Austin and the NUMA Special Projects team. But when those on site are trapped in alpine tunnels flooding with glacial meltwater, Austin can hardly ignore a cry for help. And this near tragedy proves to be no mere accident. For the body held a secret. A secret someone was prepared to kill for. Soon Austin is plunged into a mystery involving a virulent algal weed ravaging the Atlantic's Lost City trench, while he and the team face a family of astonishing greed - who will stop at nothing to get what they want...