10 years have passed since Witcher 3 and Titans started spawning. Only way to defeat them is to make powerful abomination as themselves, so mages who wield dark art gathered and summoned powerful creature named the Gray Wolf Ghoulem. As it doesn't have will of it's own it needs to be guided, so Geralt gets into it's breast cockpit and fuses with it, and in that way take it's control. There is hope.