[Caution: Spoilers about Episode 4 of The Assassination of Gianni Versace: American Crime Story ahead!]

FX's The Assassination of Gianni Versace: American Crime Story is now, and for the foreseeable future, the story of how Andrew Cunanan became one of the FBI's most wanted during his 1997 murder spree. That story becomes especially disturbing in Episode 4, "House by the Lake," which includes the gruesome depiction of Jeff Trail's (Finn Wittrock) murder, filmed more or less exactly as it happened according to the source material Vulgar Favors.

More will be explained later in the series, but Jeff, a clean-cut Naval alum who was closeted for most of his life, befriended Andrew (played by (Darren Criss) in San Francisco. Over time, he got fed up with Andrew's constant lies and manipulation and tried to cut him off. Andrew and Jeff were also friends with David Madson, a man Andrew dated briefly who eventually tried to cut him off for the same reasons. Jeff was the first person Andrew killed. It was his most barbaric attack too, ambushing him in David's apartment as depicted. But the terror didn't stop there. For several days after killing their friend Jeff, Andrew took David Madson (Cody Fern) on the run with him, and David made no known attempt to call authorities or escape.

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Cody Fern as David Madson, The Assassination of Gianni Versace: American Crime StoryCody Fern as David Madson, The Assassination of Gianni Versace: American Crime Story

As Ryan Muphy did with The People v. O.J. Simpson: American Crime Story, Versace makes decades-old events, the outcomes of which are already public knowledge, feel like they're happening in the exact moment. Darren Criss' intoxicating performance makes Jeff's murder and David's unforced captivity urgent and believable too — so much so that it's almost impossible to watch the scenes play out and not hope, scream or pray that David runs. Of course, no one can know what was said between them in some of the moments portrayed — whether Andrew constrained David with explicit threats or by psychological manipulation will forever remain a mystery. But the tragic truth is that David died at Andrew's hand. From April 27, when Jeff was murdered, until David's body was found May 3, David stayed with the man who later killed him, likely terrified. But why didn't he run? For Fern, the question was central to playing David on screen.

"I think it's such a complex bag of questions," he told TV Guide. "He was Andrew's lover. He'd experienced something traumatic — he was in shock. He was afraid for other people's lives as much as he was afraid for his life."

Cody Fern as David Madson, The Assassination of Gianni Versace: American Crime StoryCody Fern as David Madson, The Assassination of Gianni Versace: American Crime Story

David and Andrew met in December of 1995, according to Maureen Orth's Vulgar Favors. Their relationship was built on fraud and manipulation from the start: Andrew was living with an older rich man, Norman Blachford, during a good chunk of their relationship, so he didn't let David call him or send mail with a return address. Andrew plied David with gifts though, as he did many people, and indulged his S&M fantasies with David until Andrew's increasingly rough sexual demands became a source of strife between them. They broke up in the spring of 1996, but Andrew kept David's picture taped to his refrigerator door. When his life began to crumble as a result of constant deception and drug use, Andrew became fixated on the idea that David was his only love. As it happens, Andrew wasn't David's only unstable lover, either: a previous ex had become a stalker, calling David as much as 120 times a day and eventually being jailed for violating a court order to stay away. In any case, Madson was a "peacemaker," Orth wrote, a man who loathed violence and avoided confrontation. He frequently talked his way out of things.

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Vulgar Favors' intensely researched study of Andrew and David gives it license to theorize why David didn't try to flee. Andrew knew David avoided confrontation and was squeamish around violence. Orth even speculates that the handcuffs and leg restraints Andrew enjoyed could've been used to hold David captive. More than likely though, Andrew simply kept David paralyzed with fear. Experts in the book said that Andrew could've easily convinced David that he'd be a suspect if he went to police, which is exactly how Versace depicted depicted their relationship. A law enforcement official said that the brute force shown in the murder would've easily convinced David that Andrew had power over him, instilling a fear that's common in violent abusive relationships. The intense fear of retribution — even after a break — makes the Stockholm syndrome theory in David's case not at all surprising. Other issues were at play too.

Cody Fern as David Madson, The Assassination of Gianni Versace: American Crime StoryCody Fern as David Madson, The Assassination of Gianni Versace: American Crime Story

"He was also a man dealing with an intense amount of shame in the 90s," said Fern. Though David's father told Orth he never treated his son any differently after David came out to him, his religious beliefs mandated that David's sexual orientation was a sin he disapproved of. Though David wasn't religious in the traditional sense, he absorbed his dad's values. After the initial shock wore off, "[David] is asking himself, 'Is his man redeemable?'" Fern said. "He's asking himself, 'How am I complicit in this? I let my friend in — I brought him into the apartment. This my fault.'"

When he was found, David had been shot three times. Orth quotes a sergeant as saying David probably got taken by surprise: he had defense wounds on his hands and his body had apparently been dragged about 20 feet from where his killing took place. It's possible David was methodically plotting an escape — perhaps sweet-talking Andrew while psyching himself up to make a bold move. That thinking, Fern said, informs the scene with Andrew where David calls himself a coward and then attempts to commandeer the Jeep's steering wheel in a moment of desperate bravery. "The important thing to remember is that this is a man going through something more intense than anyone could ever imagine," Fern said.

It'll remain a tragic unanswered question, rooted in both men's deeply embedded shame and guilt over their sexual orientation, and fears how people would perceive them no matter what they did. "That was the whole journey of the character," Fern said. "The whole character arc is about that question. Why didn't [David] run?"

The Assassination of Gianni Versace: American Crime Story airs Wednesdays at 10/9c on FX.