A 911 dispatcher takes a panicked call from a man claiming that someone is trying to kill him in a penthouse at Central Park West. Detective Flack and a team of officers rush over, only to find a mummified corpse lying in the middle of the dusty and uninhabited apartment. Mac and the CSIs are called in to identify the mummified remains and investigate why someone left the victm in this penthouse for so many years. Sid discovers that the victim was murdered back in 1923 and Danny finds he was a venture capitalist, Walter Jones, that had stolen an invention from the owner of the penthouse, Sam Harding. Sam had died thirty years prior but was still able to keep his secret by setting up a trust that kept the property locked up after his death until the Rule Against Perpetuities ran out - this stops the deceased from owning property forever. The team realizes this doesn't explain who called 911 until a fingerprint on broken glass found at the scene leads them to an unscrupulous real estate agent, Rick Larson, who has disappeared. When they return to the penthouse they discover a series of secret rooms and puzzles that are designed to torture and kill the player if they don't answer correctly. Sam created this house for the sole intent of getting his revenge on Jones for stealing his invention and now Mac and Stella must make their way through this "death house" in order to find Rick and his girlfriend, who they have now discovered is also missing.