"This is all thanks to a Reddit Q&A," Patrick Melrose star Benedict Cumberbatch says at the film's world premiere in Los Angeles. "I was asked what characters I'd like to play and I blurted out 'Hamlet and Patrick Melrose.' I had no idea that the series was in the works, or that [series producer] Michael Jackson was interested in me for the part."

Cumberbatch immediately began prepping for his first meeting with Jackson, which required re-reading all five novels in less than a week. "I had some sleepless nights finishing up the last two books," the actor says. "I really wanted to show my appreciation for the character."

Patrick Melrose features Cumberbatch as a man struggling to overcome damage inflicted by an abusive father and the mother who condoned his behavior. Jennifer Jason Leigh and Hugo Weaving also star in the drama. The series is a co-production between Showtime and Sky Atlantic.

Cumberbatch is the first to admit that his idyllic upbringing is a far cry from the traumatic mess the character endures. "I had two very loving parents, which is a blessing. Playing Patrick and truly understanding him is something that required extensive research. I got a lot of help from a fantastic couple who advise professional bodies, as well as alcoholics and opioid addicts. They were on set at all times and a vital part of my understanding the drug paraphernalia, as well as the physical and emotional side effects of the drugs."

Cumberbatch used this knowledge to craft what he calls a "psychological backbone" for his character, allowing him to navigate through the rapid changes in mood associated with the variety of drug combinations that Patrick injects, ingests and inhales.

British TV producer Jackson and series writer David Nicholls told THR that it was a challenge to get rights to the property and, eventually, write what would become the Showtime drama. "I'd always been a huge fan of the books," Jackson says. "Once all five were completed, it felt like a saga ready to be adapted." It was Jackson's wife and producing partner, Rachel Horovitz, who fiercely pursued the property.

"Rachel and I were among several people who pitched for the adaptation rights and ultimately got them five years ago. The next step was to get David on board," Jackson said of the lengthy process.

Nicholls' immersion in the books included meetings with author Edward St. Aubyn as well as long walks through London where he'd listen to the audiobooks. "I literally listened to the books for years. It was necessary to really understand Patrick's world and take on his voice," says Nicholls, who notes his biggest challenge was truncating the material and balancing the different time periods. "The way the story leaps about time really affects how the characters evolve. A character who appears in episode one will be completely different when they appear in episode three, and even more altered by the fifth."

Nicholls' use of insightful and humorous voiceover helps bridge the gap between the real Patrick and the man he presents to the outside world. "The books are very internal; it's about an emotional journey. The character doesn't say what he feels — he's very cagey in that regard. With the voiceover, I was able to play to the audience in the same way that the books do so perfectly."

In addition to the rampant and graphic drug use, the story also explores childhood sexual abuse. Patrick's father and his horrendous deeds have reverberating effects on his adult life. "We have a flashback structure that gives the audience insights into Patrick's life, and the idea was to slowly let that seep out over the five hours…like an IV drip in a hospital," says Nicholls. "We also had to decide what to show, and how much to show."

Nicholls credits St. Aubyn with crafting five unique stories that don't necessarily fit seamlessly together. "The books are very different, and even with the smoothing of the tone, you end up with five very different episodes."

Cumberbatch and his producing partner, Adam Ackland of Sunny March, spent five months shooting the project. The globe-trotting series required several location substitutions, including Glasgow, Scotland, doubling for New York. The producers credit director Edward Berger with crafting five visually and stylistically distinct mini-movies.

Academy Award nominee Leigh portrays Patrick's mother in the drama as the character goes through a complex transformation over several decades, which was a big draw for the actress. "There were a lot of things from the novels I wanted to see brought in for Patrick's mother," she says. "I was really pleased with the scenes in France, when Patrick is a young child. Shooting with Benedict after my character has had her stroke was also incredible. Benedict is true chameleon — he completely disappears in this role."

Leigh had high praise for her leading actor, as well as the series' creative team. "There were a lot of creatives on this project, and oftentimes when everyone loves a novel, they all see the project through very different lenses. On this series, I was really surprised at how like-minded everyone was; we all seemed to share the same vision for the characters and the story," she says.

Patrick Melrose airs Saturdays on Showtime.