The Killer Revealed: 7 Shocking Twists That Made Only Murders In The Building Season 4 The Best Yet

The fourth season of Only Murders in the Building has delivered its most shocking and meta mystery to date, with the highly-anticipated killer reveal finally unmasking the murderer of Sazz Pataki. As of this December 2025 update, the season has concluded its run on Hulu and Disney+, confirming a new killer, introducing a star-studded roster of guest stars, and setting the stage for a dramatic shift for the beloved trio in the confirmed Season 5. The premise—Charles, Oliver, and Mabel solving a murder that hits painfully close to home—was just the beginning, as the true crime podcast-loving sleuths found themselves entangled in a web of Hollywood ambition and stolen intellectual property. The latest season saw Charles-Haden Savage, Oliver Putnam, and Mabel Mora leave the familiar, yet deadly, confines of The Arconia for a brief stint in Los Angeles, only to be pulled back to New York by the murder of Charles' long-time stunt double, Sazz Pataki, who was shot in Charles’ apartment. This season not only deepened the trio's bond but also introduced an explosive twist involving a hidden script, a jealous screenwriter, and a motive rooted in the very success of the "Only Murders" phenomenon itself.

The Iconic Trio: Charles, Oliver, and Mabel's Complete Biography & Net Worth

The heart of Only Murders in the Building is the unlikely friendship between three residents of The Arconia apartment building, each a celebrity in their own right, with vastly different career trajectories and financial success.

Steve Martin as Charles-Haden Savage

• Full Name: Stephen Glenn Martin
• Character: Charles-Haden Savage, a semi-retired actor best known for the 1990s TV detective show Brazzos.
• Birth Date: August 14, 1945
• Net Worth: Estimated at $140 million.
• Career Highlights: Martin is a legendary comedian, actor, writer, producer, and musician. His career spans over five decades, including iconic films like The Jerk, Planes, Trains and Automobiles, and Father of the Bride. He is one of the highest-earning members of the main cast.

Martin Short as Oliver Putnam

• Full Name: Martin Hayter Short
• Character: Oliver Putnam, a financially struggling, flamboyant Broadway director with a penchant for dramatics and dips.
• Birth Date: March 26, 1950
• Net Worth: Estimated at $50 million.
• Career Highlights: A celebrated comedian and actor, Short is famous for his work on Saturday Night Live and SCTV, as well as films like Three Amigos! and Father of the Bride. He is known for his collaborations with Steve Martin.

Selena Gomez as Mabel Mora

• Full Name: Selena Marie Gomez
• Character: Mabel Mora, a young, enigmatic artist and renovator who initially seems disconnected from her elderly neighbors but shares a past connection to the building's mysteries.
• Birth Date: July 22, 1992
• Net Worth: Estimated at $800 million (combining her acting, music, and Rare Beauty cosmetics empire).
• Career Highlights: Gomez is a global superstar, starting as a Disney Channel actress (Wizards of Waverly Place) before launching a successful music career and founding the highly profitable Rare Beauty brand. She is the highest-earning member of the trio, despite a lower salary for the show compared to her co-stars.

The Sazz Pataki Murder: Unmasking the Season 4 Killer and the Twisted Motive

The murder of Sazz Pataki (played by Jane Lynch), Charles’ stunt double, was the central mystery of Season 4, and the reveal was a classic Only Murders twist, combining a personal slight with a shocking motive.

Twist 1: The Identity of the Killer

The killer was revealed to be Marshall P. Pope, the aspiring screenwriter hired to adapt the Only Murders in the Building podcast into a movie. This reveal came in Episode 9, titled "Escape from the Building," as Mabel, Charles, and Oliver worked to piece together the final clues. Marshall P. Pope, portrayed by Jin Ha, was a new face in the Arconia's circle, making him a prime suspect for fans of the show's pattern of introducing the killer late in the season.

Twist 2: The Stolen Script and the Real Author

The motive for Sazz Pataki's murder was not a case of mistaken identity, as initially suspected, but a calculated act of intellectual theft. Sazz Pataki was the secret, uncredited screenwriter of the "Only Murders" movie. She had used her intimate knowledge of Charles, Oliver, and Mabel to create realistic, compelling scripts for the film adaptation. Marshall P. Pope, desperate for success, killed Sazz to steal her work and pass it off as his own, ensuring his name would be the one on the blockbuster movie. This twist made the crime deeply meta, as the killer's motive was to profit from the trio's own story.

Twist 3: The True Purpose of the Los Angeles Trip

The trio's brief trip to Los Angeles at the start of the season, which seemed like a fun change of pace, was actually a critical setup for the plot. They were there to discuss the movie adaptation. The murder of Ben Glenroy in Season 3 led to the movie deal, and Sazz's murder was a direct consequence of the script-writing process, linking all three seasons together through the theme of fame, ambition, and the dangers of the entertainment industry.

A Star-Studded Arconia: The Season 4 Guest Star Lineup

One of the hallmarks of Only Murders in the Building is its ability to attract A-list talent, and Season 4 was no exception. The new and returning guest stars provided crucial comedic relief and red herrings throughout the investigation.

The Returning Favorites

The season saw the welcome return of several beloved characters.

• Meryl Streep as Loretta Durkin: Her relationship with Oliver continued to be a major storyline, as she navigated her career and her future with the director.
• Michael Cyril Creighton as Howard Morris: The quirky Arconia resident and cat enthusiast remained a source of neighborhood gossip and occasional assistance.
• Da’Vine Joy Randolph as Detective Donna Williams: The no-nonsense detective continued to keep a close eye on the perpetually suspicious trio.
• Jane Lynch as Sazz Pataki: Her presence, though brief due to her character's death, was central to the plot, appearing in flashbacks and setting up the entire mystery.

The New High-Profile Cameos

Season 4 introduced an incredible array of new faces, many playing themselves or new Arconia residents caught up in the drama.

• Melissa McCarthy: Joined the cast in a significant role, bringing her signature comedic timing.
• Eugene Levy: A celebrated comedian and actor, he added to the show's ensemble of comedic legends.
• Molly Shannon: Played a key role, adding another layer of celebrity intrigue to the Arconia.
• Téa Leoni: Featured as one of the many high-profile cameos, further emphasizing the show's Hollywood theme.
• Ron Howard and Scott Bakula: Both appeared as themselves, adding a fun, self-referential element to the show's meta-narrative about the entertainment industry.

Looking Ahead: What We Know About Only Murders in the Building Season 5

Even as the Season 4 finale provided closure for the Sazz Pataki case, the show’s success guarantees more mysteries. The series has already been renewed for a fifth season, with a projected release date in late 2025. The ending of Season 4 left the trio in a state of flux:

• Mabel’s Future: Mabel Mora, having solved yet another murder, is expected to continue her journey as a successful artist, though her commitment to the podcast and The Arconia remains a point of dramatic tension.
• Oliver’s Career: Oliver Putnam's career is on an upswing, capitalizing on the "Only Murders" movie deal, offering a potential new setting or new set of suspects for the next season.
• Charles’ Peace: Charles-Haden Savage, having finally dealt with the trauma of losing his double, may find a moment of peace, but knowing the Arconia, it won't last long.

The shift from the Arconia to a Hollywood movie adaptation and back again in Season 4 proved that the show can successfully expand its world without losing its intimate, character-driven charm. Fans are already speculating whether the next murder will be a direct consequence of the movie's production or a return to a purely Arconia-based, classic true crime setup. The promise of a Season 5 means the journey of Charles, Oliver, and Mabel—the world's favorite amateur sleuths—is far from over.