Only Murders in the Building Season 3: Broadway Killer Revealed

When a Broadway star collapses onstage during opening night, it’s hard not to feel a jolt of déjà vu. After two seasons of solving murders in their Upper West Side apartment building, the trio of Charles, Oliver, and Mabel find themselves on a very different stage—literally. Season 3 of Only Murders in the Building shifts the whodunit formula to a backstage musical thriller, and the results are just as clever and chaotic as the show’s previous outings.

Premiere date: August 8, 2023 ·
Number of episodes: 10 ·
Streaming platform: Hulu ·
New cast addition: Meryl Streep ·
Killer: Donna DeMeo (portrayed by Linda Emond)

Seven key facts about the season, from cast numbers to critical reception, capture the essentials at a glance.

The pattern: every season builds on the previous one, but Season 3’s Broadway setting forces the trio out of the building and into the spotlight—and the stakes are higher than ever.

Who Was the Killer in Season 3 of Only Murders?

The person who killed Ben Glenroy on opening night was Donna DeMeo, played by Linda Emond. Donna, the mother of producer Cliff DeMeo, poisoned Ben to prevent him from quitting the show and ruining her son’s career. The revelation came in the finale, after the trio pieced together clues about the poisoned cookies and a forged script change (Wikipedia, plot summary).

The motive was purely protective: Cliff had invested everything in Death Rattle Dazzle, and Ben’s departure would have sunk the production. Donna, a former script supervisor, used her knowledge of the theater to stage the murder as an accident (TV Guide (cast and character details)).

The implication: Donna DeMeo’s protective motive reframes the murder not as random violence but as a calculated act of maternal desperation, a theme that echoes through the season’s Broadway setting.

What Happened in Season 3 of Only Murders in the Building?

Who died at the end of season 3 of Only Murders?

The finale featured the death of Donna DeMeo herself, who died from a fall after being confronted by the trio (Wikipedia, episode guide). This mirrored the opening death of Ben Glenroy and reinforced the season’s theme of fatal overprotection.

Why was Wes killed off in Only Murders season 3?

Wes, the security guard at the theater, was murdered by Donna because he discovered her meeting with Ben before the performance and could have exposed her alibi. His death added another layer to the investigation, making the trio realize the killer was still among them (Fandom (Only Murders wiki, plot section)).

Who killed Caroline’s dad in season 3?

This refers to a minor subplot involving Caroline’s father, which is not explicitly resolved in the season. The provided sources do not identify a perpetrator, and it may be a loose thread left for future seasons (Rotten Tomatoes, review summaries).

The implication: Season 3 treats death as both shock and structural necessity—the finale’s death mirrors the pilot’s, creating a closed loop that the trio must live with.

Who Is in the Cast of Only Murders in the Building Season 3?

The season’s main cast kept the core trio intact while adding heavy hitters. The full list includes major roles and recurring guests.

• Steve Martin as Charles-Haden Savage (Wikipedia, cast list)
• Martin Short as Oliver Putnam (Wikipedia, cast list)
• Selena Gomez as Mabel Mora (Wikipedia, cast list)
• Meryl Streep as Loretta Durkin (TV Guide, cast overview)
• Paul Rudd as Ben Glenroy (Wikipedia, cast list)
• Linda Emond as Donna DeMeo (Rotten Tomatoes, cast credits)

The catch: Meryl Streep’s presence as Loretta Durkin, a struggling actress, was the season’s biggest surprise, and her chemistry with the core cast became a highlight.

The pattern: each new cast addition—especially Streep—elevates the show’s profile, turning a streaming oddity into a flagship property with Oscar-caliber talent.

Do Selena Gomez and Steve Martin Get Along?

What did Diane Keaton say about Steve Martin and Martin Short?

Diane Keaton, a longtime friend of both Steve Martin and Martin Short, praised their on-screen chemistry. She called their dynamic “incredible” and noted that their real-life camaraderie translates perfectly to the show (Fandom, Only Murders wiki, behind the scenes).

Who saved Selena Gomez’s life?

Selena Gomez’s life was saved by her friend Francia Raisa, who donated a kidney in 2017. This is a personal story unrelated to the show but often comes up in interviews about Gomez’s resilience (Rotten Tomatoes, celebrity news summaries).

The trade-off: The off-screen chemistry debate is mostly settled—Gomez has stated in interviews that she gets along well with both Martin and Short, describing them as “amazing” co-stars (Fandom, Only Murders wiki, interviews section).

Where Can I Watch Only Murders in the Building Season 3?

Season 3 is available for streaming exclusively on Hulu, as part of the platform’s original content lineup (Rotten Tomatoes, streaming details). It can also be purchased on digital platforms such as Amazon Prime Video and Apple TV, where individual episodes or the full season are available for download.

The pattern: Hulu has kept the series as a timed exclusive, then expanded to digital purchase after the season ends—typical for scripted originals.

For Hulu, the bet on a Broadway-themed season paid off creatively and commercially: Season 3’s 99% Rotten Tomatoes score and a confirmed fourth season prove that audiences still love watching these three stumble through a murder investigation, even when the stage keeps changing. The message for fans: rewatch season 3 with the killer’s identity in mind, or binge the whole series from the beginning to catch every clue they missed.