When Bo learns that a Fae is running a sort of dog fighting ring, but with humans in place of the dogs, she gets involved and discovers that the owner of the boxing gym, a Light Fae named Ferraro, is in The Ash's inner circle. Although Bo is certain that Ferraro is feeding some Fae steroid to a human fighter named Mike, Dyson won't be able to help her unless she's able to bring hard evidence to support her case.
Kenzi has a fight of her own when a figure from Bo's past shows up and proclaims Bo to be a monster. The woman is Mel, the sister of Bo's first love. She's been tracking Bo from city to city, and when Kenzi can't convince Mel that Bo is not this "Beth" who was complicit in her brother's death, she takes her to see Hale, certain that he'll sing Beth into silence. But since Bo hasn't declared herself as Light, Hale can't protect her.
Moments later, Bo walks into the station with hard evidence for Dyson - a power shake made for Mike that she's sure has some kind of Fae juice in it - and comes face to face with Mel. Hale manages to get Mel detained for a psych evaluation, but not before she spits insults at Bo. The reminder of those she's killed is too much - Bo runs home and packs a bag, preparing to leave town once more in an attempt to escape her past. The only thing that can stop her is Dyson's information that the shake contained a serum from a frog Fae. If Mike gets angry, as he's likely to do in a fight, he'll die. Mike has an adopted son, but there's no mother in the picture. Bo knows she has to keep Mike from fighting in order to keep the boy, Tyler, from becoming an orphan.
She shows up at the match just as Mike is getting in the ring. Dyson has told her that Tyler is Fae - his birth parents were killed in a car wreck, and Mike was the volunteer firefighter that rescued the boy but was unable to save the parents. On a hunch, Bo asks Tyler if he put his own sweat into Mike's shakes, and the boy confesses, saying he didn't want to see his dad get hurt again. Bo wins his trust by telling him that she's Fae, too, and tells him how much danger Mike is in. Tyler rushes into the ring and stops the fight by revealing his frog Fae identity.
Bo stops at the Dal to say goodbye, but Hale stops her with the news that Mel now thinks Bo was running from a serial killer in the area. Bo is furious at Hale, but Trick steps in and says it was his doing. Bo breaks down and tells him that the Nain Rouge gave her a vision in which she killed him. Trick tries to brush it off, but is certainly shaken.
Because Ferraro's human fighting ring was broadcast online, The Ash needs to handle the situation. He neutralizes Ferraro.