The Opera is a mod for the popular FPS computer game Half-Life. As opposed to the "hop around like a madman and shoot anything that moves" feel of a traditional deathmatch, or the heavy devotion to realism seen in mods such as Counterstrike, The Opera aims for a feel of "movie realism".
The atmosphere of the game is modeled after the Hong Kong Blood Opera genre, seen in such films as Face/Off and The Replacement Killers.
Mechanics of the game are designed around the principle that "a couple of shots should kill you but you should be able to do amazing things to prevent that from happening."{1} Players will be limited to realistic speeds most of the time, but will be able to perform various stunts, such as rolling and diving, limited by a slowly recharging "Action Meter". In addition, players will be able to buy various special abilities, called Shticks, such as "Lucky Shot" or "Endless Ammo".
The Opera is scheduled for release in mid-September 2000.
{1} Quotes taken from The Opera's official site: http://www.halflife.net/opera