I can now tell you who is my actual secret agent (and let her go afterwards). It's Sif the goddess. Go visit her, she might know where those plate pieces are, that you love so much. Drive on!
Tasks:
Talk To Sif (In Sif's Retreat)
Description:
I'll give you some of my precious time. My cooperation with Heimdall's adjutant is at an end and that's why I promised to help you. I've seen one of the plate pieces behind the blue gate. The key to it is lost somewhere here.
Tasks:
Find A Plate Piece (In Sif's Retreat)
Talk To Sif (In Sif's Retreat)
Description:
I thought that a weakling like you will be eaten by some bear in a second. But let's get back to our agreement. The other plate piece should be behind the rusty gate. The key is missing again...
Tasks:
Find A Plate Piece (In Sif's Retreat)
Description:
In order to continue with this quest, you have to go back to Fjordheim town.