Season 4 of Only Murders in the Building has officially come to a close. This season offered its usual mix of twists, mysteries, and star-studded cameos, keeping audiences engaged as it slowly revealed the tragic fate of Sazz (Jane Lynch).
As we reach the season’s end, we finally discover who killed Sazz, why the crime happened, and what secrets have been hiding in the shadows all along. With the murder now solved, the series even sets the stage for a fresh mystery, promising more excitement ahead.
In the previous episode, the season’s penultimate one, viewers learned that Marshall (played by Jin Ha) was the murderer responsible for Sazz’s death. The revelation came after a season of suspense, where Marshall had remained a relatively low-profile character.
His motives, hinted at but never fully understood, have been a topic of much speculation among fans. The finale provides the full picture, showing not only why Marshall committed the murder but also what drove him to act as he did. And as the season closes, a brand-new mystery unfolds, with stakes as personal as ever.
Charles and Oliver Spring into Action to Save Mabel
The final episode begins by picking up where Episode 9 left off, with Mabel (Selena Gomez) discovering a script for the Only Murders movie that includes Sazz’s name. She quickly confronts Marshall about it, but at that very moment, she receives a text from Charles (Steve Martin).
The message reveals to her that Marshall is not only Sazz’s protégé but also her killer. Episode 9 ended with this cliffhanger, leaving Mabel alone with Marshall, unaware of the danger. Meanwhile, Charles and Oliver (Martin Short) remain oblivious to the situation, unknowingly putting Mabel at even greater risk.
At the start of the finale, Charles and Oliver are discussing whether Mabel has received their message warning her about Marshall. Soon, however, they get a response — but it’s not from Mabel herself.
Instead, Marshall has intercepted the message and responds using Mabel’s phone, telling Charles and Oliver that if they come near or call the police, he will kill her. Faced with this terrifying threat, Charles and Oliver are determined to act and refuse to leave Mabel in harm’s way. They quickly come up with a plan to save her.
Charles recalls that since Marshall was a stuntman, it’s possible he scaled the building’s ledge to reach Charles’s apartment and murder Sazz. Despite his fear, Charles feels he has no choice but to do the same. Though he couldn’t save Sazz, he believes he can still rescue Mabel.
Charles and Oliver’s Daring Attempt to Save Mabel
To improve their chances, Oliver suggests that Charles start from the apartment of Vince (Richard Kind), which is right next door to Mabel’s. This means Charles would have less distance to cross along the ledge, reducing the risk.
In summoning his courage, Charles begins inching along the ledge, speaking to himself and asking Sazz for strength and guidance as he goes. He openly admits his doubts, stating he doesn’t think he can manage this alone, and that he could use her help.
At that moment, he feels a hand on his shoulder. Initially, it appears that he may be experiencing one of the ghostly visions of Sazz that have been recurring throughout the season. However, it turns out to be Oliver, who has joined him on the ledge to offer support.
Together, the two make their way to Mabel’s apartment, while Mabel herself manages to distract Marshall by criticizing his script. Knowing he is obsessed with becoming a successful writer, she points out flaws in his work, which distracts him enough to buy Charles and Oliver precious time.
Marshall is so wrapped up in the idea of fixing his script that he agrees to let Mabel help — though he still plans to kill her afterward.
As Marshall is distracted, Vince and Rudy (Kumail Nanjiani) also lend a hand, creating an additional diversion. With Marshall’s attention elsewhere, Charles and Oliver are able to slip into Mabel’s apartment, bringing her to safety in a daring rescue.
Marshall’s Shocking Motive for Murdering Sazz
Once Charles and Oliver enter the apartment undetected, they manage to overpower Marshall using an unusual tool — a 19-in-one multitool created by Eva Longoria.
Charles uses it to wrestle the gun away from Marshall, ultimately putting him at a disadvantage. This unexpected move shifts control to the trio, giving them a chance to interrogate Marshall about his motives. Finally, he explains the sequence of events that led to Sazz’s death.
Marshall tells them that, following an incident involving Ron Howard, Sazz had encouraged him to focus solely on his writing. She even went so far as to read his latest work and offer feedback. According to Marshall, Sazz had found his writing so inspiring that she decided to try writing her own script. She later shared this script with him, the only existing copy, and asked for his opinion.
Marshall admits he initially had low expectations. Sazz was a stunt performer, not a writer, so he assumed her script wouldn’t be particularly special. However, after reading it, he was shocked to discover how talented she was. Her script was better than anything he had ever written.
This realization stirred a sense of jealousy in him, and when she asked for his feedback, he lied and claimed he would make edits, even offering to make a copy for her.
In truth, Marshall was so envious of her talent that he decided to steal her work. Over time, he made numerous “edits,” eventually changing the author’s name from Sazz Pataki to Marshall P. Pope. When he sent the altered script to others in the industry, it eventually reached Bev Melon (Molly Shannon), who loved it and wanted to turn it into a movie.
But Sazz eventually learned the truth. Hurt by the betrayal, especially after she had mentored him and taken him under her wing, she confronted Marshall. The situation became even more painful when Sazz realized she hadn’t even asked for Charles’s permission to try and sell the script.
Her anger grew, and she decided to take a trip to New York to see Charles’s Broadway debut and tell him about the script in person. Fearing that her revelation would ruin his career, Marshall booked a last-minute flight to New York to prevent her from exposing him.
Because Sazz had written about the Dudenoff apartment in her script, Marshall knew how to find Charles’s building and gained access to the apartment, where he confronted Sazz. He shot her when she entered, believing this would be the end of his troubles. But Sazz didn’t die right away.
Charles had suspected correctly — Marshall had to scale the building’s ledge to reach the apartment, where he questioned Sazz in her final moments. When he asked where her original script was, she used her last words to warn him that her “number one” would come for him. Marshall, unsure what this meant, left the scene but continued to fear the consequences of his actions.
A Last-Minute Twist: An Unexpected Hero
After listening to Marshall’s confession, Charles loses his temper and hurls the multitool at him. However, the tool misses, creating enough chaos for Marshall to regain control of his gun. He then holds the trio at gunpoint, taunting them with the line, “Welcome to the end of your movie.” It seems as though he’s ready to pull the trigger and finish what he started.
But before he can act, an unseen figure intervenes. The surprise assailant who saves the day turns out to be Jan Bellows (Amy Ryan). Jan, as fans will remember, is Charles’s former girlfriend. As it turns out, she never left Charles’s apartment after their breakup.
Instead, she had been hiding in his closet and moving through the walls of the Arconia for three weeks. Her presence, though surprising, becomes the key factor that turns the tables in the trio’s favor, ultimately preventing Marshall from causing further harm.
Moving Forward with the “Only Murders” Movie
With Marshall now defeated, Charles, Mabel, and Oliver turn their attention back to the Only Murders movie project. Despite the problems that have plagued the production, they decide to continue with the film, this time basing it on Sazz’s original script.
The Hollywood team begins rehearsing scenes, using dialogue that feels truer to the characters we’ve come to love. As the production moves forward, Charles receives one last vision of Sazz on the set.
He apologizes to her for her absence and offers her a symbolic writer’s chair as a tribute to her work. It’s a touching moment, filled with bittersweet emotion, as they share a final farewell and honor their enduring friendship.
A Wedding, A New Mystery, and a Startling Discovery
After the intense events surrounding Marshall’s capture, the episode shifts to a more celebratory tone. Oliver is preparing for a wedding, an event that brings a sense of joy after the season’s heavy moments. He’s concerned, however, due to a warning from Charles that implied Loretta (Meryl Streep) might be the next target.
For a moment, the show even toys with this possibility, especially when Loretta is slow to make her way down the aisle. However, these fears turn out to be unfounded. The wedding proceeds without incident, and Oliver walks down the aisle accompanied by Charles and Mabel. He and Loretta exchange vows, sealing their commitment to each other.
Though the wedding is a happy occasion, Loretta has one important request for Oliver: she doesn’t want him to move to New Zealand with her. Her reason is not a lack of affection but rather an understanding of Oliver’s need to stay close to Charles and Mabel, as they share a bond that transcends friendship.
Once the wedding concludes, the show hints at a fresh mystery. A woman steps off the elevator and approaches Charles and Mabel, identifying herself as Sofia Caccimelio (Tea Leoni). She tells them her husband, Nicky Caccimelio, has gone missing, and she needs their help to find him.
When Charles and Mabel remind her of their number one rule — they only investigate murders that happened within the building — Sofia insists her husband’s disappearance is connected to the Arconia. She hands them her card and asks them to reconsider.
Initially, it appears that this case will set up Season 5’s central mystery. But the very next morning, Charles and Mabel stumble upon another discovery. As they wrap up their podcast episode, they realize they made it through an entire wedding without any unexpected deaths.
But then they come across the body of Lester, the beloved doorman, lying in the building’s fountain. Charles and Mabel’s horrified expressions reveal that this new case will indeed take place within the Arconia, paving the way for a new investigation.
With its latest season wrapped up, Only Murders in the Building leaves fans with both a sense of closure and anticipation. As Charles, Mabel, and Oliver continue their sleuthing adventures, the mystery of who killed Lester will surely keep audiences guessing in Season 5.
Conclusion
Season 4 of Only Murders in the Building delivers a finale packed with tension, humor, and heartfelt moments, wrapping up one mystery while teasing the next.
The reveal of Marshall as Sazz’s murderer, driven by envy and ambition, gives a fittingly dramatic end to this season’s story arc. Through Marshall’s twisted confession, the show shows the darker sides of mentorship, ambition, and betrayal, highlighting the depth of relationships within the Arconia’s walls.
Charles, Oliver, and Mabel’s bond strengthens further as they show a series of clever twists and unexpected dangers.
Their rescue of Mabel showcases the trio’s bravery and loyalty, proving that their friendship can survive even the most harrowing situations. Meanwhile, Jan’s surprising reappearance adds a nostalgic layer, tying together multiple seasons with her unexpected heroism.
With Sazz’s legacy preserved in the Only Murders movie, the characters honor her memory in a touching way. Yet, just as they begin to find closure, the wedding and the mysterious death of Lester reveal that the Arconia’s secrets are far from exhausted.
Sofia Caccimelio’s request hints at even more intrigue, but Lester’s sudden death makes it clear that this murder mystery will keep our detectives right where they belong: within the building’s familiar walls.
As we await Season 5, Only Murders in the Building continues to excel in blending suspense with humor and heartfelt moments.
With fresh mysteries now at their doorstep, fans can be sure that Charles, Mabel, and Oliver are set for another unforgettable chapter in their crime-solving journey. This finale reminds us that in the Arconia, there’s always another story waiting to be uncovered.
