Stabler and Benson investigate the brutal assault of a man outside a strip club. The doctor informs the detectives that the man received severe trauma to the crotch area and is now in a medical-induced coma to help cope with the pain. The victim had no ID, only a photo of him with a young boy, identified on the back as the man's five-year-old son, Henry.
A witness helps Stabler and Benson establish that their John Doe was a tow truck driver and return back to the scene of the crime to retrieve his truck. The truck reveals the man was a slob, making it harder to collect fingerprints from inside. They also find a tire iron with blood and hair on it. Meanwhile, the man's business papers are inside the glove department and they find out their John Doe's name is Mark Van Curen.
Mark awakes from his coma but cannot recall any of the events before his attack. Mark believes his soon-to-be ex-wife, Ellen, had something to do with the attack. They were both in the middle of a bitter custody suit for their son, Henry, who is now 13. After a visit to Ellen's house, she denies any allegations of attacking Mark, but admits she has threatened him in a fit of rage.
Ellen tells the detectives that Henry is transgendered and now going by the name Hailey. She has accepted Hailey for who she is, but Mark has not, therefore Mark wants custody to send his child to therapy. She also admits that Hailey snuck in her room at 2:00 a.m. on Monday night and hit Ellen when she tried to find out where she was. Benson tells Ellen that Monday was the night of Mark's attack. Hailey refuses to answer any of the detectives' questions, but does say she wishes her father really were dead.
Stabler and Benson discover Hailey has been having violent outbursts in school; she later admits to the assault of her father. But, without a parent present, the admission is inadmissible. A search warrant is issued for Hailey's house and detectives find boxes of stolen hormone injections. Her mother later admits that Hailey joined the group suspected in the thefts, "The Children of Ariel."
Stabler meets the leader of "The Children of Ariel," Blake. He tells Stabler that Hailey helped participate in the raid against the pharmaceutical plant on Monday night, making it impossible for Hailey to have attacked her father. Back at the precinct, Blake tells Hailey it's not her fault for Blake's arrest. Hailey keeps telling Blake she loves him, as he's taken away to interrogation.
Mark rushes to the SVU and tells Ellen he wants Hailey to live with them, but Hailey says she knows about Mark's affair with a stripper. When Stabler wants to know how Hailey found out, she says her guidance counselor, Jackie Blaine, told her. When Stabler and Benson question Jackie on knowing about Mark's affair with a stripper the night of his attack, she admits she's the one who assaulted him.
Hailey rushes to the SVU to rescind her statement about Jackie telling her about Mark's affair. Hailey tells Benson that she just ruins lives and begins to feel faint. Benson notices that Hailey has cut her wrists and she is rushed to the ER. Ellen is at a loss as to what she should do, since Mark still wants custody. Benson assures Ellen she'll help find her an attorney to represent Hailey.
Jackie's attorney has painted her client as the perfect guidance counselor who is always there for her students. Greylek tells the detectives that if she wants to win this case, she needs to call Hailey to the stand. Benson points out that Hailey isn't stable enough for testimony, but it's Greylek's only hope.
Stabler tries to talk to Hailey about Mark's feelings. Hailey asks Stabler what she would do if Stabler's son came home in a dress. Stabler says there's nothing his son could do that would make him stop loving him. Hailey cries into Stabler's arms.
Back in court, Hailey tells the jury that she never wished her father harm. But, during cross-examination, Jackie's lawyer points out that Hailey tried to kill herself eight times in the last five months and each time, told Jackie her father was to blame and she wished he was dead. The defense points out that Jackie attacked Mark, thinking she was protecting Hailey.
Jackie is called to the stand and continues to stick by her story that by attacking Mark, she was saving Hailey's life. She tells Greylek that she knows what Hailey is going through and admits that she, too, is transgendered. She tells the story of being sexually mutilated years ago by three strangers, as a punishment for being who she was. Her testimony brings tears to Hailey's eyes.
After Jackie's explosive testimony, Mark takes Greylek aside and asks her to drop the case against Jackie. Mark now realizes what his daughter has had to go through and he feels horrible now, knowing he was trying to keep her hormone blocker from her. Mark has now recognized his son is really a girl and has accepted it. The detectives urge Greylek to put a plea bargain on the table for Jackie.
Jackie accepts the plea bargain and is sentenced to eight years in prison. Before she is escorted out of the courtroom, Hailey tells Jackie that her father is now allowing her to take the hormone blockers she needs to become a woman. Both Mark and Ellen escort their daughter home.