The Surgeon

That night, Anne lies restless with Derreck. He reassures her that a security team found no listening devices in their house. Anne reveals that Paula visited her office, providing statistics about her surgeries. Derreck becomes angry and demands that Anne never speak to Paula without a lawyer, but Anne convinces him not to interfere.

At 3:07 am, Anne wakes and drives to the hospital. In the basement security office, she meets Mike, a young officer who helps her review security footage from Donaghy’s room the night before his surgery. Before leaving for a smoke break, Mike warns Anne not to touch the delete and import buttons.

While watching the footage from Donaghy’s room, Anne recognizes the silhouette of a nurse in the hallway and follows her via the camera feeds to the operating room where Donaghy died. Inside, the nurse uses a syringe to inject the cardioplegia solution into the port. Anne uses the security interface to delete the incriminating footage and replace it with earlier footage. She deletes as many segments showing the nurse as possible before Mike returns. When he returns, Anne lies about her purpose. Mike jokes about looking for a killer, and Anne forces herself to laugh.

The next morning, M storms into Anne’s office and reveals that security identified who called the SAO: Lee Chen, Anne’s surgical nurse. M summons Lee, who confesses that Paula caught him with a DUI and extorted him using his mother’s immigration status. The deal was made last October, before Donaghy’s surgery. Paula coerced him into reporting any issues with Anne’s cases and later demanded that he find something she could use; Lee gave her resuscitation statistics from the peer review.

M demotes Lee but says she’ll keep him employed, as his testimony could prove Paula’s investigation was a setup. She puts Anne on notice to figure out why the SAO is targeting her or risk losing her tenure.

That evening, Anne confronts her mother, who admits that she knew Donaghy’s identity. Anne’s mother explains that they discovered on Melanie’s first night with them that she had been sexually assaulted. Anne’s father, Bill, sedated Melanie so that they could examine her without further trauma. They reported the abuse to the police, learning that the foster father’s name was Caleb Donaghy, but without Melanie’s testimony, nothing could be done.

Her mother reveals that Bill spent four years getting Donaghy removed from the foster parent directory. When she saw Donaghy’s name on Anne’s patient notes, she concluded that he had to die. Anne hugs her mother and confesses to her role in ensuring his death.

Anne’s mother asks how she knew who the patient was. Anne explains that she recognized Donaghy from his unique birthmark, which she first saw in a park when Melanie reacted to his presence with terror. She realized that the abuse was rape after seeing a TV show as a teen.

Anne confesses her guilt over Melanie’s death by suicide, which occurred after her first date. She happily helped Melanie get ready, but failed to warn her about boys or potential triggers. She later found Melanie’s body hanging from a bedpost. Anne’s mother insists that Donaghy killed Melanie and mentions the possible security video at the hospital. Anne reveals that it’s gone and asks what was in the syringe; her mother confirms that it was potassium.

Derreck arrives as Anne and her mother toast to justice and to Melanie. Anne reflects that some secrets aren’t hers to tell.

After dinner, Anne updates her mother and Derreck about Lee’s extortion. Derreck becomes enraged. Anne receives an urgent text from M with a video link. The video shows a press conference featuring Paula, then cuts to Derreck at the same event. A brief clip shows them speaking to each other.

Derreck calmly claims that he runs into Paula only at professional events, temporarily allaying Anne’s suspicions. Anne texts M, asking where she got the video. M replies that it came from an anonymous sender.

The following Wednesday, Paula waits in Anne’s office with a gun, planning to confront Anne when she’s emotionally vulnerable. She looks at the photos on Anne’s desk, including one that shocks her. Derreck storms in, revealing that Adam Costilla sent him to stop Paula. Derreck confronts Paula about extorting Lee and orders her to leave.

Paula positions herself to see Anne approaching, but blocks Derreck’s view. When she spots Anne, Paula grabs Derreck and kisses him passionately. Derreck shoves her away, but Anne has seen the kiss. Anne enters, looking pale. Paula pulls out her gun and orders Anne to sit down.

Anne sits, realizing from Derreck’s hesitation that he isn’t innocent. Derreck tells Paula he filed a sexual harassment complaint that morning. Paula points the gun at his chest. Anne diverts Paula’s attention.

Paula reveals that she’s Melanie’s biological sister. Her investigation has been a 25-year quest for revenge after Anne’s family “took” Melanie by adopting her. She saw Anne on a billboard, found her, and then discovered Melanie’s death certificate. Anne realizes that Melanie’s childhood letter to Santa asking to see her sister was about Paula. Paula points to a photo showing herself in the background on adoption day.

Paula reveals that she has been sleeping with Derreck for seven months to destroy Anne’s life. Driven by emotion, Paula swipes everything off the desk, scattering papers from Donaghy’s file. Paula sees Donaghy’s photograph and freezes in horror. Anne realizes that Donaghy also abused Paula. After shredding the photo, Paula insists that someone must pay for her sister’s death.

Derreck, furious at being used, lunges for the gun. It fires, grazing his abdomen. He gains control and presses the gun against Paula’s chest. The gun fires again. Paula collapses as the police storm in. Anne finds that Paula has a weak pulse. As Derreck is taken away, Anne reflects that she no longer knows who he is.

Anne sits with the unconscious Paula in the intensive care unit (ICU), learning that she’ll fully recover, and vows to help her fight the charges she faces. Returning home, Anne enters Melanie’s bedroom for the first time in 20 years, opening the curtains. She begins packing Derreck’s suitcase, intending to divorce him.

Derreck returns from the police precinct, where he faced no charges. He gives Anne roses, but his eyes have a cold determination. He brings up Donaghy’s name, implicitly threatening to expose Anne’s role if she leaves him. Anne tells him that she wants a divorce. Derreck dismisses this, suggesting that they both forget each other’s transgressions.

He pours wine and toasts to them being together forever. Anne feigns compliance. Derreck adds a toast to Caleb Donaghy. As Derreck drinks, Anne smiles, realizing that he thinks he has won. She reflects that only one of them knows a dozen ways to make a heart stop without leaving forensic evidence, and it isn’t him.