Wolfenstein: Enemy Territory was one of the great multiplayer shooters of its day, delivering what was at the time uniquely class-based, objective-based gameplay. It came off the back of the success of singleplayer Return to Castle Wolfenstein, but it was multiplayer only—at least, it was at the time. It had an unfinished singleplayer campaign cut during development, long considered lost, but with the recent revival of Wolfenstein: Enemy Territory by modders one man, William Faure, is bringing back that dream.
This follows on the heels of a major mod project, called RealRTCW, that remade Return to Castle Wolfenstein itself.
Faure is taking the six Enemy Territory maps and making them into both singleplayer and cooperative experiences. He's not a stranger to modding the game, either, because he's the person behind an extensive RealRTCW mod called The Dark Army: Uprising, an unofficial sequel to the RTCW story. Given the trailer above, which shows not just a slice of game from several maps but an extended look at gameplay on a D-Day level, it's coming along nicely.
You can read more about it on this Steam post by the RealRTCW team. You can track the mod's progress on its moddb page. Wolfenstein Enemy Territory Singleplayer will release on November 19th 2021, and come to Steam on November 30th 2021.