This mystery can be found in the northwest of Lincolnscire, just south of the Lacestone synchronization point.
When you arrive at the mystery location, you’ll see two Norse Soldiers tied up in the Saxon camp. As it turns out, these are the same brothers who you encountered during The Twit Saga, Part 1. The first objective is to kill all the Saxons in the camp and rescue the brothers by untying their bonds. One of the brothers is unconscious, so you’ll need to carry him out of the camp and follow the other along the road to the south.
As you run southward you may encounter a pack of wolves, so you’ll need to place the unconscious brother on the ground while you fight them off. When the conscious brother asks you to stop, speak with him to complete the mystery.