Detective Rainy Night is an indie adventure game where players assume the role of police officer Iker Carmona. Carmona is investigating a series of strange disappearances that lead him to the isolated Motel Holiday during a severe storm. The game spans five days and is structured into 12 narrative-driven levels. Gameplay centers on deduction, interrogation, and piecing together clues to unravel the mystery.

The narrative unfolds at the Motel Holiday, trapping Carmona and seven guests during a worsening storm that disables all communication and transportation. Players must interact with the guests, gather information, and recall events to solve the case. The game incorporates mature themes, psychological horror, and unexplained phenomena.