Michael Douglas was older at the time of filming than Liberace was when he died. Although played by 42-year-old Matt Damon, Scott Thorson was only a teenager when he met Liberace, and 23 when their relationship ended in April 1982. He was still only in his twenties when Liberace died.
There was some concern during production about how Liberace's heavy cigarette smoking would be depicted, as Michael Douglas had vowed to quit the habit after being told his cancer was in remission in January 2011.
In a January 2013 interview with the New York Post, director Steven Soderbergh said that the film was originally intended for theatrical release, but was ultimately produced by and aired on HBO instead because the story was seen as "too gay" by all of the major Hollywood studios: "Nobody would make it, we went to everybody in town. They all said it was too gay. And this is after Brokeback Mountain (2005), by the way, which is not as funny as this movie. I was stunned. It made no sense to any of us." Despite this, the film was selected to compete for the Palme d'Or at the 2013 Cannes Film Festival, where it received its worldwide premiere. It was also theatrically released in Europe and the rest of the world.
In May 2013, the New York Times reported that Scott Thorson received a little less than $100,000 for his participation with this movie, and that he spent all of that money "in about two months, mostly on cars and jewelry."
According to an interview with Michael Douglas at the Television Critics Association Winter Press Tour, Debbie Reynolds, who plays Liberace's mother in this film, was personally acquainted with the real Liberace and appeared as a guest on his variety show. Douglas also said that when he was younger, his father, Kirk Douglas, had a Palm Springs home down the street from one of Liberace's homes, and although Michael Douglas never met Liberace, he did occasionally see him in the neighborhood.
In an interview with Entertainment Weekly, Rob Lowe described the make-up regimen used to transform him into the heavily plastic-surgeried Dr. Jack Startz: "It's tape and pulled behind my head. It's literally what they used to do in the early days of cinema before there were facelifts for actresses. You know, Joan Crawford, her whole career was this. You tape, you pull around the back of the head, but you have to have a wig because it covers the elastic. We did that, and I'm also wearing a dental piece and then I'm doing a couple of things, a couple of tricks with my own face, the way I'm holding it. Then of course the makeup is literally like Earl Scheib autobody paint sprayed on my face....It was actually really painful, because being pulled that long and that hard for a 12-hour day - it gave me migraines. We shot during the summer. It was unbelievably hot. The wig, being pulled, it was definitely not the most comfortable experience physically for sure."
Steven Soderbergh is particularly famous for his fast rhythm shooting and editing, with ideas clearly conceived beforehand and no running over schedule. According to Matt Damon, filming was completed on a Friday and Soderbergh had edited a first cut by the following Monday.
The New York Times obituary for composer Marvin Hamlisch, who died on August 6, 2012, revealed that before Hamlisch's death, he had already completed the score for the film, which did not air until almost a year after his death. The film is dedicated to him.
Costume designer Ellen Mirojnick and her team had to reproduce a large number of Liberace's iconic stage outfits for this film. These included a copy of Liberace's 16 foot-long white virgin fox fur coat, which, though made of synthetic fur, was nonetheless, like the real coat, studded with $100,000 worth of Austrian crystals. The originals were too valuable to alter to fit star Michael Douglas, and were used only as set dressing for Liberace's walk-in closet. Many were also extremely heavy due to the large quantities of rhinestones: each original suit weighted upwards of 60 pounds.
Liberace's Beverly Hills penthouse was shot on location in the real apartment space. The art department was able to recreate the apartment's original black and metallic look based on photos provided by the owner, who was a huge Liberace fan.
The Liberace Foundation in Las Vegas owns many of the original portraits from the pianist's famous home. However, the paintings which appear in the film are all recreations, with the original facial features altered to resemble Michael Douglas.
Special effects were used to digitally graft the actor's head onto the body of Philip Fortenberry, a Juilliard-trained Liberace virtuoso who was the in-house entertainer at the (now closed) Liberace Museum in Las Vegas for years.