FX’s “The Assassination of Gianni Versace: American Crime Story” was a long and grueling shoot that stretched from May to January, hopscotched the country from Miami to Minnesota to Chicago to San Francisco, and was lensed virtually all on location. The houseboat where Versace killer Andrew Cunanan was trapped as he met his end was rebuilt from scratch on Miami’s Collins Avenue by the production team, based on crime scene photographs and other footage from the era of the 1997 slaying of the famed fashion designer.

But all of the time, energy and money devoted to “Versace” paid off for uber-executive producer Ryan Murphy, once he saw how star Darren Criss, writer/exec producer Tom Rob Smith, and director/exec producer Dan Minahan pulled off the final hour of the nine-episode series.

“It was that moment when you’re shooting the series that you’re waiting for. We knew the stuff Darren was going to have to do would be very, very emotional and upsetting, when he was finally caged and trapped,” Murphy told Variety. “It was hard for him. Darren had nobody to react to other than himself for most of the episode. He really arced the character so well and stripped it down to the bare essence at the end. It was very emotional and difficult material. Darren gave the performance of the year.”

Murphy said he’s gratified to see Criss receive generally strong reviews for the extremely demanding role that he hopes will open more more doors for the former “Glee” player.

“When you get stereotyped as a writer or an actor it’s hard to break out of that lane and show people you’re capable of so much more,” said Murphy. “I’m excited for him about what opens up for him.”

Murphy also hailed Minahan and Smith for taking the extra step of intense rehearsals for the climactic scenes of Cunanan alone as a squatter in a houseboat as the FBI’s manhunt closed in on him. “Versace’s” narrative unfolded as a backward chronology from the moment of Cunanan’s July 1997 murder of Versace on the steps of his Miami mansion. Smith immersed himself in research to write all episodes of the series in that challenging format — an accomplishment that drew a thumbs up via Twitter earlier this week from none other than Stephen King.

The final hour of the series, “Alone,” depicted the moment of reckoning for the deranged protagonist as well as some closure for other characters, including Donatella Versace (Penelope Cruz), Marilyn Miglin (Judith Light), Cunanan’s hustler friend Donnie (Max Greenfield), and Versace’s lover Antonio (Ricky Martin). Murphy said those sequences were designed as “arias” to give the supporting characters a final bow in the spotlight.

“Max Greenfield came back with this thesis statement about homophobia, Judith Light gave us this insane operatic monologue,” Murphy said. “We spent time with the victims, the people who lost things because of Cunanan’s murders.”

“Versace” did not land with the same pop culture punch as the inaugural “American Crime Story” series, 2016’s “The People V. O.J. Simpson.” To date the series has averaged about 3 million total viewers in Nielsen’s live-plus-7 ratings, compared to about 7.7 million for “People V. O.J. Simpson.”

Murphy said he knew that the “Versace” would draw a more modest crowd given the subject matter and the fact that the Simpson saga was so much more well known by the general public. But the larger message of “Versace’s” effort to demonstrate the homophobia and discrimination that hampered the police investigation of Cunanan’s killings has touched a nerve, based on the reactions Murphy has received.

“I can always tell if something is working or landing by how many people stop me on the street to tell me they’re binge-watching it and loving it,” he said. “I’m so proud about the message of the show. It meant a lot to people.”

The conclusion of “Versace” comes on the same night that another new Murphy production wraps its freshman year. Fox’s “9-1-1,” a fast-paced procedural about first-responders and dispatchers, couldn’t be more different than “Versace.” Murphy admits he was reluctant to do a traditional network TV procedural, but prodding from Fox Television Group chairman Dana Walden made Murphy’s team pull together a strong cast — anchored by Angela Bassett, Connie Britton, and Peter Krause — and deliver “9-1-1” for debut sooner than they expected in January.

“Dana was really adamant in saying ‘You have another procedural in you’ and that Jan. 3 was the time to premiere it,” Murphy said. “And she was right. Dana is the reason why this has all worked.”

“9-1-1” has inched up steadily in viewership, winning its Wednesday 9 p.m. time slot for most of its run with an average of 10 million viewers. Murphy said there’s already discussions of potential spinoffs — every major city has a first-responder hub, after all — but nothing formally set in stone. In the near term, the focus is on expanding the show in season two with “more people in the call center and more stars,” he said.

With “9-1-1,” Murphy has launched a hit for Fox in his waning months as a producer on the lot before he segues to a mammoth Netflix overall deal on July 1. Murphy hasn’t had time to hatch any brand-new ideas for his new network home — he’ll have his hands full during the next year delivering the four new shows — two for Netflix — that he already has in the pipeline in his soon-to-expire 20th Century Fox TV deal.

At present Murphy is in New York shooting the 1980s-set drama “Pose” for FX. In July he’s slated to begin work on the political satire “The Politician” and the eighth season of FX’s “American Horror Story.” When those shows wind down in January, he’ll reunite with Sarah Paulson on Netflix’s “Ratched,” the origin story of “One Flew Over the Cuckoo’s Nest’s” Nurse Ratched.

So while he won’t be actively developing new projects for at least a few months, Murphy won’t exactly be idle.

“There’s going to be a lot of extensive legwork and a lot of traveling for these shows. They all shoot in different cities,” Murphy said. “For the first time in a long time, I can tell you I feel pretty content. For now, I’m good.”