Marv narrates how New York is full of heinous crimes, so much so that they all blend together -- but sometimes a killer stands out.

At The Pickle Diner, the Arconiacs lament that the Only Murders podcast has been floundering. Marv gets annoyed that the others don't believe his theory about the 6th Avenue Slasher being Bunny's murderer.

Sam, Paulette, and Grant discuss other podcasts. Marv accuses them of disloyalty.

Mabel runs in and hugs Charles and Oliver. Marv leaves the Arconiacs' table and heads over to the trio.

Marv narrates about the 6th Avenue Slasher, who killed during the early '00s, targeting victims on 6th Avenue, as well as the rest of Manhattan.

As Marv approaches the trio, the lights go out. Charles says they have to get to Lucy.

Marv informs them the whole Eastern Grid is probably out. Ivan comes out of the kitchen with candles to let everyone know that power is out in the entire Tri-State area.

No one has cell service. Oliver gets an email with his DNA results, but it won't load.

Marv offers to talk the trio through his 6th Avenue Slasher theory, but they brush him off.

As the trio heads out, Ivan calls after them, carrying an armload of dips, asking Oliver to take them (for free) as they will go bad without the fridge power.

Marv narrates that the 6th Ave Slasher targeted older women, as well as younger women and men of all ages. He was never caught.

Lucy explores the apartment in the dark.

Down in the Arconia lobby, Lester keeps getting calls. A crowd has formed, and Ursula deals with the irate residents. To appease them, Ursula hands out Gut Milk.

Nina calls the front desk and asks Lester to bring her her package. He balks, noting she's on floor 14. Nina's baby cries. Lester says he'll be up.

Mabel, Charles, and Oliver return to the Arconia.

Charles and Mabel head to the stairs. Oliver is resistant but follows after some insistence.

Howard chats with Dr. Stanley, pointing out an attractive man who is subletting on his floor. Howard is enamored, and Dr. Stanley urges him to ask the man out. Howard thinks the man is out of his league.

Dr. Stanley suggests asking for batteries to light his lantern. Howard is nervous, but Dr. Stanley urges him to live life to the fullest.

Mabel, Charles, and Oliver climb the stairs. Oliver has to stop around the fourth floor, lamenting the potential reveal of Will's paternity.

Charles and Mabel insist that Lucy needs them and they should continue upwards. Oliver sits, claiming bad knees. He and Charles realize they both have the same knee-replacement surgeon. Mabel gets them back on track.

Oliver tells them to go on without him. Charles suggests leaving the dips behind. Oliver says a dramatic goodbye to his dips, and the trio continues upwards.

Lucy tries to text Charles again, but there is still no service.

Howard tries to feed Sevelyn, but she won't eat because it's not warm.

Howard psychs himself up to ask the handsome subletter, and as he opens the door, the man is standing there. They are both startled but laugh when they realize they were both were going to ask the other for batteries. Howard offers his visitor candles and invites him in.

Lester arrives at Nina's apartment with the package -- a baby swing. Lester asks to sit as he's exhausted after climbing 14 flights of stairs. Nina begrudgingly allows it.

Lucy hears a noise. Someone is trying to get into the apartment. Lucy calls for Charles, but there is no response. The intruder starts banging on the door. Lucy runs for the bathroom. The intruder bangs open the door.

On floor 11, Oliver states he can't go on. Mabel and Charles help him up.

The intruder shines a flashlight around the apartment. Lucy crawls into the secret passageway. The intruder heads into the bathroom and follows in through the passage.

Mabel, Charles, and Oliver arrive at Charles's apartment, calling for Lucy as they realize the door has been broken open. They check the bathroom and assume "glitter guy" has gone after her.

Amid candles and wine, Jonathan, the handsome subletter, asks Howard if he's the one he hears yodeling. Howard explains that Jonathan may have heard him practicing for his yodelshop group, and explains what yodelshop is. Jonathan tells Howard he has a beautiful voice.

Jonathan shares that he plays a Hyena in The Lion King on Broadway. He says it's great but sometimes exhausting, and he has often considered becoming a children's librarian. Overcome, Howard reveals that he is a librarian.

Lucy heads through the passageways with the intruder in pursuit. She hides. More footsteps approach.

Lester sets up Nina's baby swing. Lester tells Nina he enjoys helping people, despite Nina thinking he's useless.

Lester asks her what she's working on, and she explains it's paperwork for the new construction that will be taking place soon.

Lester mentions his wife, and Nina remembers her name. Lester is surprised, but Nina says Bunny always quizzed her on the residents, and she rattles off Lester's kids' names and interesting facts about them.

Lester says Bunny was the best. Nina and Lester wonder who could have killed Bunny. Lester feels responsible because he must have let the murderer in. The baby starts to cry again.

Mabel, Charles, and Oliver go through the passageways, still looking for Lucy. They get lost. Oliver sits, needing a rest. Charles and Mabel sit as well. They worry that they are nowhere near to solving the murder.

Jonathan asks if Howard was singing "The Sound Of Silence" yesterday. Howard tells him it's the finale to their upcoming Simon and Garfyodel concert. Jonathan asks him to sing a bit, but Howard shyly refuses, saying he never sings alone. Jonathan suggests they duet.

They begin to sing the song together, and the sound travels out the window and through the courtyard of the Arconia. Ursula and the residents in the lobby join in.

Oliver comes in with "In restless dreams…" but Charles and Mabel shush him. Jonathan and Howard continue their duet. Nina's baby stops crying. Oliver continues in hushed tones, and Mabel sings quietly as well.

Jonathan and Howard go in for a kiss when Jonathan suddenly starts sneezing. He asks if Howard has a cat, as he is deathly allergic.

Lucy runs down the passageway, finding Charles, Oliver, and Mabel.

Jonathan leaves, thanking Howard for a great blackout.

Lucy leads them through the passageway, telling them about the intruder, and she thinks it was the person she saw in the passageways the night Bunny died.

Charles is shocked that Lucy was in the Arconia that night. They realize she saw the killer. However, she didn't see the killer's face or notice anything strange about them except that they sneezed.

Mabel says they need to get somewhere safe. A light appears behind them. Someone is approaching. Charles, Mabel, Oliver, and Lucy run.

With the figure in pursuit, Lucy leads them out of the secret passageways and down the stairs.

On the way down, Mabel spots Oliver's bag of dips. As the figure come down the stairs, Mabel hangs back and clocks them in the face with a heavy bag of dips.

The lights come on.

Mabel removes the person's half-face respirator mask. It's Marv.

Lester gets up to leave Nina's. He notices the "space pod" artist's rendering, remarks on it, then offers to mail some of Nina's letters. Nina offers him the future position of Director of Resident Support. He is warm to the idea.

Howard lint-rolls his sweater and knocks on Jonathan's apartment door. Jonathan answers.

Howard suggests that he could send Sevelyn to live with his friend for a while and remove all cat remnants from his place if Jonathan would go on a date with him. Jonathan agrees, assuring Howard he doesn't need to get rid of his cat.

Marv swears that he did not kill Bunny, and the trio asks him to explain why he was chasing Lucy. Marv insists he was trying to protect Lucy from the 6th Ave Slasher. The strange outfit is his work clothes -- he's a mold inspector. When they mentioned they were worried about Lucy, Marv went up the back way, having done work in the building.

Lucy tells them that Marv isn't the one who was chasing her. Marv says he just wanted to be part of solving the case and hoped to rekindle a relationship with his daughter. Lucy says that Marv did scare the killer away with his flashlight. Oliver offers to get Marv in to record some of the next episode.

The trio discusses the four times they have seen the killer, wondering if the killer and Glitter Man are the same person. They realize Lucy is not with them and then spot her chatting with Detective Kreps.

Kreps and Lucy approach. Kreps says Lucy was telling him about the goings-on. He says he was just in the neighborhood checking in on them, and warns them to be careful.

Charles and Oliver go off with Lucy, leaving Mabel with Kreps. She is dubious as to why he was in the area. Marv, behind them, grabs a Gut Milk.

Kreps mentions that he saw the subway stabbing video and asks what's stopping him from locking her up. She says she was wondering the same thing. Kreps tells her that he enjoys interviewing teenage girls (like Lucy).

Howard and Jonathan walk by, heading to The Pickle Diner, and accidentally bump into Kreps's arm. The detective rubs his upper arm, wincing in pain, saying he got a new tattoo.

Marv watches suspiciously. Kreps speaks rudely to Marv. Mabel notices some red glitter on the Kreps's neck. Kreps wishes Mabel a good night and leaves. Mabel, in shock, bids him goodnight as well.