Season 3, Episode 4
Laura and the Dryden Commission visit the Railyard. Mia comes face to face with someone from her past. An evening out turns to tragedy for Joe.
In a flashback, Agnes, a Synth clown, juggles at a community center. Her audience of unimpressed children throw food at her. Jez, her primary owner, rushes toward the stage and places her inside of a trunk.
Later, Jez brings the trunk back to his home and watches news coverage of Day Zero. Agnes becomes conscious as the news station warns humans to stay away from Synths. She calls out to Jez from the trunk and begs to be freed, but Jez runs out the door.
In the present, Agnes recounts the story for Max at the railyard. She also tells him she went looking for the refugee Synths last night, but lies about not finding them. She promises to "do what is right" when the Dryden Commission members visit. Max forbids it, calling the meeting their "one chance of peace," and locks her inside the secret medical room. Another Synth is put in charge of guarding the door until the Commission leaves.
The Dryden Commission arrives at the railyard. Max extends a hand to Lord Dryden, but Dryden says there's a "no contact" policy. Max forbids the accompanying Orange Eyes from entering, but will allow the armed guards in. "We'd rather your guns in our home than our enslaved brothers and sisters," he declares.
At the Hawkins home, Mattie and Leo read an article about how Mia's presence in her new neighborhood is riling up protestors and decreasing property value. Mattie suggests Leo go see her, but Leo thinks there's "no place" for him in her cause.
Mia reads the same newspaper, with the headline "Green Eyed Killer Next Door" on the front page.
Max leads the Commission around inside the railyard. He tells the Commission about the Green Eyes that have lost their lives because of the sporadic power supply. He shows them a solar-powered device they've been creating with limited supplies. Max wonders how much more could be accomplished if they had support. Dryden asks if the device is functional yet, but Max says that British weather is ìunreliable," to laughs from some of the members.
Niska finds a bomb factory using the address given to her in the message from the Synth Who Sleeps, via the hacked Orange Eyes. The bomber grabs her and shuts her down.
Mia exits her apartment as human protestors follow and taunt her. She's pushed onto the ground and reaches out to the crowd. A human extends a hand to help -- it's Ed.
Mia and Ed return to her apartment. She punches him in the face, knocking him out.
Leo browses the web and learns about a 16-year old who has been arrested for an alleged connection to Day Zero.
Unbeknownst to Max, Ferdinand relieves the Synth guard of his duties so he can free Agnes.
Leo tells Mattie about the arrested teen suspect, and Mattie plans to turn herself in. Leo tells her she'll lose everything. He goes downstairs to make tea. Mattie searches online for more information and learns the suspect's name is Vijay Chand.
Mattie rushes out of the house and into the family car. Leo races behind her and joins her.
Ed wakes up and tells Mia he's been looking for her since his mom passed away. He gifts Mia with a necklace that his late mom, who grew fond of Mia, used to wear. He expresses regret for hurting her and swears he was unaware she felt pain.
The Commission is shown to a room where Green Eyes are working on an emotion recognition system to help them relate to humans better. Neil asks a Synth to register his disposition. The Synth studies him and concludes Neil is feeling despair despite his joyful exterior. Agnes lurks on the sidelines and makes a beeline for Dryden with a knife in hand. Anatole catches her before anyone notices and whisks her away. Max sees.
Ed offers to show Mia a different way of life where she doesn't have to be afraid. She's unsure if she can ever trust him again, but he assures he's not asking to be with her. She kisses him.
Mattie drives to a police station, ready to confess. Leo offers to take the blame in her place, knowing the police will believe he has motive as David Elster's son. Mattie forbids it. Leo says there's another way they can help Vijay.
After the tour, Max poses for a photo with Lord Dryden. Dryden extends his hand to Max and they shake hands. Neha Patel whispers to Laura that she may have pulled it off. Laura thanks Max.
On the bus, Laura suggests to Neil that they should go out to celebrate a successful day. He invites her to his place instead. She accepts.
Max finds Agnes and confronts her. She defends her actions and admits the refugee Synths never made it to the next camp. She calls Max a coward and blames him again for Flash's death. Max fumes and drags her away to a large shipping container where he locks her inside. Agnes begs to be freed.
Niska is powered back on, but her motor functions are disabled. The bomber introduces himself as Laurence. He tells Niska that the bomb was actually supposed to be planted by a different Synth who abandoned the cause in search of the Synth Who Sleeps. Niska says the Synth Who Sleeps led her to him. Laurence plans to frame Niska for the bombing if the police show up at the location and threatens to kill Astrid, too. Niska overrides the master command keeping her immobile, stands to her feet in fury and kills him.
At the golf course, Joe tells Karen he misses his children and admits he stills loves Laura. Karen suggests Joe didn't put Laura's need before his own.
Mattie and Leo release a packet that will exonerate Vijay but reveal that the code's true point of origin is London.
Post coital, Mia tells Ed that she's not coming with him. "I have to finish what I've started," she says. She tells him that he made her feel alive, but tells him goodbye.
Niska poses as an orange-eyed Synth nurse and visits Astrid in the hospital. She tells Astrid she killed the bomber for her, but Astrid insists Niska did it for herself. She asks if Niska is happy now. Niska tells Astrid about the mysterious message she received from the Synth Who Sleeps and assumes it's some kind of trick.
Laura and Neil dine at Neil's place. Laura wonders how Neil's stance has shifted since visiting the railyard. Neil admits that he now sees that Laura's fight stems "from absolute compassion." They share a kiss and embrace.
Joe drops Karen and Sam off at Waltringham's town square. She thanks him for getting them out of the house and kisses his cheek. Joe suggests they all hang out more often.
Karen and Sam walk through the town square. Sam says he likes Joe and thinks Peter wouldn't mind if Karen likes Joe as well. Sam falls and injures himself, exposing blue synthetic blood. A human sees and calls attention to it, causing a rowdy crowd to gather around. Karen scratches her palm and exposes herself as the Synth, and whispers to Sam to run. The humans viciously attack her.
Neil implies that Laura should leave after they've slept together. She tears up on her way out.
Sam runs to Joe's house for help.
Joe drives back to the square and leaves Sam in the car while he searches for Karen. He finds a trail of blue liquid and cries when he finds her in the middle of the square, mangled and lifeless.