 Brian suffered severe psychological trauma due to the experiences in the container and was left in a mental institution, where over time he became a violent psychopath, resulting in him also becoming a brutal murderer, even more dangerous than Dexter himself.Upon being released, he went underground, refining his ability to kill and taking on the identity of a plumber he killed (Rudy Cooper) as an alias, all while searching for his brother.Eventually, Brian not only discovered Dexter's location and history upon being separated, but also discovered he was similarly "damaged"; upon learning this, Brian immediately plotted to reunite with Dexter for the purpose of killing people side by side.