This takes place when the Circus first opened, in 1952

Thomas a tightrope walker up on the highest tightrope, performing his favorite trick, a leap from one end of the rope to the middle of it, then dancing along the rope for the remaining section of the rope. He had practiced this trick hundreds of times before, and this wasn't his first time performing it infront of a large crowd. However, this time, he lost his footing and slipped. Noone knows how this happened, since they'd taken precautions that were supposed to keep him from slipping and falling. However, they had all failed. Thomas had slipped, and began falling over a hundred feet to the ground, landing on top of Damien, who had been performing below. Thomas had landed on damiens head, smacking his own head on a platform at ground level, cracking his skull open, killing him instantly. Damien slowly bled out, part of his spine sticking out through his neck, and his lungs slowly began to fill with blood, as he began to die slowly.  Instead of calling for an ambulance, the Owner of the circus began to act like the incident was all part of the show and that the two of them were perfectly fine. Then, once all of the guests had left, he hid their bodies and removed the two of them from all posters and promotional material, essentially erasing them from the circuses history completely

Fast forwarding to the current year, 2023, Damien and Thomas are both haunting the circus. Thomas has lost his ability to think and speak, and Damien is holding a grudge against Thomas for ruining his performance and killing him, and with the circus, for not taking extra precautions, like a safety net, and for not getting him to the hospital in time. The two lost souls are permanently bonded together, with Thomas forced to go wherever Damien went, for all eternity. Damien has made it his mission to kill every single performer in the circus, in the most gruesome ways possible, by ruining their acts, which would result in Fatal accidents. He can't harm the contortionist for some strange reason, though.