Episode 4 of "Memory of a Killer" unfolds with Angelo coercing Wesley into making a call to the man he sold bullets to, ultimately tying him to a chair and interrogating him about The Ferryman. Herc, the man in question, defiantly refuses to reveal anything about the enigmatic figure. He even challenges Angelo to kill him, knowing that The Ferryman could inflict harm not only on him but also on his family. Reluctantly, Angelo turns his attention back to Wesley and mentions a power plant.
The next morning, Angelo visits Maria's house, where he observes tension between her and Jeff. To cover up his involvement from the night before, he lies to Maria, claiming to have a phone issue. He attempts to check up on his daughter but is met with a lie from Maria, who says she's listening to a podcast to help her process her trauma.
Later in the day, Maria arrives at the shooting arena where she meets Dave and opens up about her mental health struggles. She's deeply affected and wants to learn self-defense from him, believing that Angelo and Jeff won't understand what she's going through. Dave receives a call from the police station about the shooter who attacked her not long after, and they head to the station together.
Meanwhile, Joe and Angelo are discussing their next target, an arms dealer named Katherine Morton. Joe provides Angelo with details about Katherine's work and her upcoming meeting. Angelo decides to focus on killing Katherine during her spa session before an arms deal. However, Angelo reads a coded message on Herc's phone that he picked up before killing him. The two decide to investigate the power plant mentioned in the message, which is located on Willow Road. Angelo calls off the hit and warns Joe against questioning him further.
In this tense and emotional episode, each character's motivations and fears are brought to light, adding depth to the already complex storyline of "Memory of a Killer."
At the police station, Dave informs Maria that Henry Bloch, the man who shot her, has been found dead in the river. The FBI had already been investigating Henry, which prompts Maria to speculate if he was murdered. She tries to press for more information, but Dave dismisses her inquiries.
Angelo arrives at the power plant, determined to uncover who Herc was working for. He kills two of the three goons there and attacks the third, Leo. Leo falls and hits his head on a rock, bleeding out. Angelo demands to know who ordered a hit on his family. Before dying, Leo reveals that The Ferryman was after Angelo due to a personal grudge.
Angelo picks up the files that Leo and his men had with them, shocked to see recent pictures of Maria, Jeff, and Michael. It indicates that his family is being surveilled by The Ferryman.
That night, Angelo is at his apartment with Nicky. She comments on his secrecy and knows he is hiding his real family from her. He quickly points out that this isn't an affair and lies that he doesn't have kids. Angelo tells Nicky that his wife passed away, and the two end up in bed.
The next morning, Angelo visits Michael at the nursing home and asks Michael's doctor to reach out if someone comes looking for him.
Maria heads to the river where Henry Bloch's dead body was discovered. She finds a shoe there and calls Dave to tell him about it. She thinks Henry fell off the bridge and asks Dave to check it out. Dave's superiors give him a tongue-lashing about Maria's involvement in the investigation and ask her to go back home as the cops investigate the case.
The following day, Joe was left in a state of distress after Angelo had backed out on their plans. Angelo, in a bold move, shot the men who were supposed to meet the arms dealer, Katherine. He cleverly posed as the customer seeking to purchase weapons from her and attempted to secure her signature on the deal. When Katherine tried to flee at the threat of violence, it proved futile. Angelo proceeded to eliminate both her and her bodyguards.
Next, Angelo tasked Joe with hacking into Herc's phone to retrieve vital information. At their home, Jeff opened up to Maria about his concerns for her wellbeing. He broke down in tears and urged her to consider therapy, even suggesting a move to another state. This proposal upset Maria, but Angelo's arrival and suggestion that Jeff had discussed the move with him only reinforced Maria's belief that they were safest in Hudson Springs. She refused to flee or be cowed, which impressed Angelo with her strength.
Before leaving, Angelo mentioned to Jeff about setting up the crib, surprising Jeff who reminded him that it had already been done previously. Jeff returned to his apartment and called Jane, Michael's doctor, inquiring about treatments for Alzheimer's. Jane mentioned clinical trials, but Angelo didn't reveal anything about his own memory loss. He offered to accompany Michael during his musical therapy sessions.
The FBI arrived at the power plant where they discovered the three dead bodies left behind by Angelo. Linda believed that the three bodies had been staged to appear as if they had killed each other. She added that one person was behind all three murders and had deliberately set the scene to hinder their investigation.
That night, Dave informed his superior that Henry had been murdered based on the blood found on the bridge. Joe arrived at Angelo's apartment with Leo's phone and the two men engaged in a conversation while sharing a drink.
The episode concluded with Angelo making a call using one of the numbers on Leo's phone, and he was shocked to hear Nicky's voice on the other line.
