Nikolai created more messes than he could ever clear up, but family was family, and Cas couldn't turn his back on him. Alas, he arrived on Dormero Station to find Nikolai dead, but his debt to local crime boss, Valen Massio, very much alive. 

On the hook for the money, Cas is stuck working for Massio to pay it off. It's a simple job, all he has to do is deliver the package that got his brother killed, while evading both Massio's bloodthirsty rival and the Federal Security Service.

Piece of cake, right?