In Memoriam (released as Missing: Since January in the US) is an adventure video game for Windows and Macintosh developed by French studio Lexis Numerique. It uses alternate reality-style gameplay, in which the player receives emails from other in-game characters, including the game's main antagonist. The player needs to find information and clues to the games' puzzles on the Internet, both from real websites, and from specially-created websites that have been mixed in with other "real-world" domains. According to director Eric Viennot, the game was a commercial success, with sales above 300,000 units worldwide by late 2006.