The game will be powered by Unreal Engine 5.
CD Projekt Red has announced the next installment in The Witcher series, continuing the beloved RPG series. According to the announcement, the next part of the franchise is already in development and will "kick off a new saga for the franchise."
Unlike The Witcher 3 and Cyberpunk 2077, the studio's previous iconic releases, The Witcher 4 will be powered by Unreal Engine 5 instead of REDengine. The company also plans to closely collaborate with Epic Games' developers to help tailor the engine for open-world experiences. Despite that, the company doesn't plan on making the game an Epic Games Store exclusive.
Unfortunately, no further details regarding the game's development time frame or release date are available as of right now. You can read the full announcement here.
UPD: CDPR's Global PR Director Radek Grabowski commented that the next game will not be called "The Witcher 4". According to Radek, the fans should wait for a new saga in The Witcher franchise, not necessarily a continuation of Geralt's story. As for right now, the company refuses to discuss any specifics in terms of story, characters, mechanics, or plot details.