Hidden Deep is an action-adventure platformer with elements of horror, survival and a side view. The game takes place in a research complex two kilometers under the ocean floor. One day, scientists discovered something strange, as a result of which an expedition was organized to study an anomaly of unknown origin. However, after a certain time, communication with her was interrupted. You have to lead the second team, whose main goal is to find out what happened to their predecessors and save everyone who managed to survive. You will be able to control team members directly or give them orders. The game has both a story mode with missions on randomly generated levels, and the possibility of cooperative play. In addition, there is a survival mode.