Dregnaught

A wise old man with a much older friend takes over a captured alien spaceship and they set out on a mission to find new worlds and restore peace on worlds that were victims of the ship's former owners. In the process, they must battle more of the enemy aliens as well as make friends with the previous victims. Some of those victims have long memories and are as much or more dangerous than the aliens at first contact. The mission requires the friends to recruit highly talented people to help them operate their ship.