Description taken from PC version of this game

The Messenger lets players take the role of Secret Service Agent Morgan Sinclair to guide her through a dangerous and highly sensitive mission. The objective is to infiltrate the famous Louvre Museum to recover four very special, very powerful artifacts. Known as "Satan's Keys," when these four ancient items are joined together they have the power to initiate nothing short of Armageddon. Gameplay involves riddles and puzzle solving, punctuated with character actions and 3D cut-scenes that reinforce the dark, clandestine mood of the game. ~ T.J. Deci, All Game Guide