Everyone is headed home to their families but Hailey feels alone.
Hailey asks Trudy for overtime.
It's a montage of her repatedly taking overtime
Hailey takes on a narcotics bust with a unit, and is annoyed with a guy who partners with her and wants to know if there are openings in Intelligence.
When they hear gunfire, they head into the building to back up the others. They give chase.
Hailey chases after a suspect and ends up in a basement in a warehouse. She finds a teenage girl tired up to a dirty mattress and tries to help.
The girl tells her to run and someone knocks Hailey out from behind.
When Hailey comes to the girl is gone and Intelligence picks up the case to find the girl.
They get a lead at the house where they find Sean, who Hailey learns is Chief O'Neal's son and he runs a youth center for at risk youth and is looking for her.
The Chief goes off on Voight about Hailey bringing his son in and questioning him and everyone in the bullpen can hear it.
Sean offers to help Hailey and brings her to his center to give her a file.
She talks to the teens who are Abby's friends, and gets a lead with Abby's friend.
Things escalate with Sean and Hailey and the kid.
Sean tells Hailey that his father told him Hailey is going off the deep end.
They get a possible lead with a guy with no record. They head to his home and look around, but he's not there. Hailey finds images of Abby on his computer. He's trying to sell her for sex.
Sean calls Hailey to tell her that Abby called him and told him where she is and he's headed there. Hailey and Kim go to meet up with him.
They get there but they must've just missed Abby.
They get another lead and track down the guy.
Tey hear gunshots and Hailey makes her way up to the roof where Abby is. She killed the guy holding her captive.
She's freaking out and Hailey tries to talk her down.
It seems to be working until she mentions Shawn. Abby jumps off the roof after that.
Hailey pieces together that Sean may be the dangerous one. She looks into his kids and finds a bunch of missing ones that may not have slipped through the cracks but may be gone beause of him. She tells Voight.