|“|| "I'm not sure I'm getting the strategy here..."|
"You're the strategy, Parrish. You're the one in the fresco-- put there as a reminder that the Beast isn't unstoppable. Whoever painted it, they didn't see a guy with a gun facing down the Beast. They saw you. They saw the Hellhound."
At some point in history, a prophecy was foretold of a great battle between the Hellhound and the Beast of Gevaudan, which was then depicted in a fresco painting buried within the walls of the tunnels under Beacon Hills, California. Under the feet of the Hellhound and the Beast in the painting is a pile of dead bodies stacked up on top of one another, though the victor of the battle is not depicted.
The war between the two creatures of the night began shortly after the successful completion of Mason Hewitt's Chimera transformation, successfully making him the vessel of the resurrected spirit of the original Beast of Gevaudan, Sebastien Valet, who was killed in 1767. However, Sebastien's spirit was weak and unable to initially remember his own identity, which led the Dread Doctors to induce transformations into the Beast upon Mason, as each time he shifted, Sebastien would grow stronger and more aware of who he truly was. During this time, the Hellhound, now possessing the body of Jordan Parrish, engaged in battle with Mason in Beast form on several occasions, all of which ended in Parrish being injured due to Cerberus, the Hellhound possessing him, not fully merging with Parrish's spirit.
Shortly after Cerberus agreed to merge with Parrish and allow him full access to his power, Mason was able to transform without the Dread Doctors' prompting, giving Sebastien the strength necessary to allow his spirit to overpower Mason's and transforming the latter's body into that of the former. Now in full control of his new body, Sebastien was able to have his first battle with Parrish/the Hellhound, which once again led Parrish to become moderately injured and allowed Sebastien to flee. After learning that the Argent Family had the pike that could kill him, Sebastien became curious about the fresco and forced Hayden Romero to take him to see it. Upon learning that the Hellhound was prophesied to battle him, he realized that the Argents would try to give him the pike with which to end his life once again and made it his mission to find them.
During their next fight in the underground tunnels of Beacon Hills, they were evenly matched, with Parrish even beginning to overpower Sebastien when they grappled. However, upon hearing Lydia Martin's scream when Theo Raeken attacked her, Parrish became distracted enough that the Beast could beat him back.
In the final battle, Lydia arrived and used her Banshee voice to give Mason's spirit full control over his body again, expelling Sebastien's spirit from within him. Sebastien's spirit then became a dark cloud of vapor in the shape of his Beast form and attempted to flee until Parrish ran toward him and wrapped his arms around the cloud, somehow managing to restraint it as though he was a corporeal being. This hold lasted just long enough for Scott McCall to throw the pike like a javelin, plunging its blade into the cloud and killing Sebastien for good once again.
- Though the Hellhound and the Beast were prophesied to do battle with each other, Jordan and Sebastien did not actually meet face-to-face until Season 5's The Beast of Beacon Hills.
- It was the desire to have this prophecy fulfilled that caused the Dread Doctors to start creating Chimeras, which meant that Jordan and Sebastien's battle was the ultimate goal of the events throughout Season 5.