Old Flame follows the characters of Sarah and Jack, who were once deeply in love during their college days, but went their separate ways after a mysterious incident that left them both traumatized. Years later, the two reunite at their college reunion, where they try to pick up where they left off and reignite their old flame.
However, as Sarah and Jack begin to spend more time together, they start to uncover the truth behind the incident that drove them apart so many years ago. As they delve deeper into the mystery, they realize that the danger they faced in the past is still very much alive, and they are forced to confront their fears and traumas before it's too late.
Caught in a web of lies, betrayal, and deceit, Sarah and Jack must fight to survive as they are hunted down by a group of ruthless individuals who will stop at nothing to protect their deadly secret. In a race against time, the two former lovers must work together to uncover the truth and overcome their past before they become the next victims of the sinister plot unfolding around them.