Private detective Tex Murphy is hired to investigate the murder of a university professor. It turns out that he was one of eight scientists involved in Project Overlord, a mission to remotely control people. Tex soon learns of the deaths of other related figures. Suspects may include the British intelligence head, a surveillance company owner, and the professor's daughter. Tex's first adventure takes the player through the seedy West Coast world of 2033, a setting that combines futuristic elements with film noir and hardboiled detective fiction styles. The game's main adventure portions are icon-driven, with object puzzles less significant than detective deduction and character interaction. Characters are represented by digitized photos. Mean Streets features dozens of characters to interact with by asking questions or offering bribes. Fights often arise, but a diplomatic approach is more successful with characters whose guilt is unproven. Although it is largely an adventure game, travel between cities involves piloting Tex's Lotus Speeder in a flight simulation section. The game also contains side-scrolling action sequences where Tex has to eliminate a number of enemies before being able to proceed to the destination.