The release trailer contains minor spoilers, so to understand why Remi ends up being interrogated, you can watch the story trailer at the link.
Hell is Us is set in the fictional country of Hadea, torn apart by war between the Palomians and Sabinians, where a mysterious Catastrophe has also occurred. Remi enters this chaos, fighting Hollow Walkers in search of his parents, but gradually becomes drawn into something much bigger.
The game offers no hints or direct guidance: players must explore the environment, interact with NPCs, and gather clues to advance the story. There are also Dungeons full of dangers and puzzles that must be solved to progress.