I'm facing a problem in the game and can't fix it!
I bought Hjerim in between the completion of "Blood on the Ice" mission. I had sent Wuunferth to jail (only by showing the journals to Ulfric's Steward). After that, I bought Hjerim and found the strange amulet. The 4th victim never appeared outside Candlehearth Hall and, as a way to fix this bug, I went to speak directly with Wuunferth, and the dialogue option "the killer has struck again" was available. As predicted, Wuunferth told me to look for the killer that very night. During the night, the quest marker led me to Calixto, running towards Hjerim (from god knows where, for I saw him running past the Candlehearth Hall as I made my way from the Palace of the Kings), and hides himself in the secret room! Inside my house!! Fortunately he did nothing to my wife... But then he becomes invincible and never goes out! He just stands there, attacking me when he notices my presence and never goes away! I had to move my wife from there... ¬¬