Underwater hunting continues! Despite the fact that hunter Roman Savelyev was dismissed, depth awaits him again. A forgotten bottom missile launcher, preserved from World War III, threatens to launch a nuclear strike on Europe. The authorities are powerless in the face of a terrible threat, and only former underwater hunters and veterans are able to develop a plan to eliminate it. But to implement this plan, you will have to risk a lot, come into conflict with the law and even collude with a biotechnological mutant monster. Every step on this path is mortally dangerous, because the depth does not forgive mistakes...