Only Murders in the Building Season 5 Episode 3 Ending Explained: Who are the billionaire mobsters?

Only Murders in the Building Season 5 premiered on 9th September 2025 on Hulu. This popular comedy drama stars big names like Steve Martin, Martin Short, and Selena Gomez, with guest appearances from Meryl Streep, Richard Kind, Nathan Lane, Bobby Cannavale, Renée Zellweger, Logan Lerman, Christoph Waltz, Téa Leoni, Keegan-Michael Key, Beanie Feldstein, Dianne Wiest, Jermaine Fowler, and more.
Other series regulars, such as Michael Cyril Creighton, return as Howard Morris, as do Da'Vine Joy Randolph (as Detective Donna Williams), Nathan Lane, and James Caverly (as father-son combo Teddy and Theo Dimas).

Only Murders in the Building Season 5 - Recap

This dark comedy murder mystery has just released its episode 3, which introduced the billionaire mobsters. While Charles, Oliver, and Mabel continue the investigation.
The episode titled “Rigor” starts with a voiceover by Charles, who reveals that when cars arrived, the horse stables that were under Arconia became quite quaint.
How the city's mobsters transformed them into a covert gambling club, the Velvet Club, which began operations in the 1910s and lasted for a century, hosting significant figures and witnessing decision-making for the city. The mob witnessed in some iconic performances like those of Lucky Luciano, John Gotti.

While investigating, Charles and Mabel find out that the velvet room is underneath the cleanups because they were able to hear Oliver wailing through the vents. They decide to return to Charles’ apartment after doing their own bits in the new murder investigation, but Oliver finds himself in a difficult situation as he discovers that his fingerprints are on Nicky’s corpse. He is left with a rotting corpse, with which he runs into Uma, who questions him about his panicky demeanour and stressed sweating sarcastically, he blames it on menopause.

Later in the episode, the trio is seen performing an autopsy on Nicky’s body just to find out all the horrifying things that happened, like rope marks on the wrist, a burn mark right behind the ear, and a gardenia on his coat lapel, which proved that Nicky’s death was recent. They were able to connect Nicky’s death to that of Lester, as there was something common in both the corpses, which included Arconia stationery. Oliver and Mabel stay focused on their mission to find the culprit, which Charles struggles with hallucinations of Nicky commenting on how lonely his life is and how he lacks morals.
There is a catch, as the trio barely makes it in time to return the corpse to the cleanup crew. They doghe paparazzie and police investigators. They overhear the police suggesting that the Caputo family is a suspect. Meanwhile, Oliver takes a ledger from Randall, which has coded betting data linked to the obscure Velvet Room.

Only Murders in the Building Season 5 - Ending explained

The end of the episode unfolds many new mysteries, and it is shown that the trio enters the velvet room for further investigation and in the hopes of finding the mobsters, but instead encounters a top billionaire like Sebastian “Bash” Steed (Christoph Waltz), who is a tech wizard who is obsessed with immortality. Next in the velvet room are Jay Pflug (Logan Lerman), who is a pharmaceutical heir, and Camila White (Renée Zellweger), a hotel magnate who "owns half of New York."

In the end, these people are revealed as billionaire mobsters who are underground operators, pulling strings all across the city. Concluding the episode with a cliffhanger and dropping some new clues, like Jay missing a finger, which is interconnected to a clue that the trio found earlier.

These new revelations are trickier and much messier than the other murders that took place in the buildings, as previously the motives that were attempted were based on personal motives, but this time the trio is pitted against people who have limitless resources and also who fear none.
The main question here is not just who the murderer is, but also why such powerful people will become a part of such shady crimes.
This episode had many new revelations that make the storyline full of new adventures and strengthen the gritty murder mystery, with a mix of comedy, suspense and some star-studded guest appearances.
 

Episode 4 will release on Tuesday, 16th September 2025.
Stay tuned!