Nicole Kidman and Mark Strong on ‘Nine Perfect Strangers’ flashback

This article contains spoilers for season 2, episode 5 of Nine Perfect Strangers, titled “Prague.”

As the brilliant (yet deranged) wellness guru-turned-trauma therapist Masha Dmitrichenko (Nicole Kidman) hurtles a new batch of guinea pigs ever closer to catharsis (or cataclysm), Nine Perfect Strangers looked to the past this week. But the revelations from the second season’s big flashback episode have only ratcheted the drama up.

Titled “Prague,” the episode provides clarity around the enigmatic relationship at the center of season 2 between Kidman’s Masha and Mark Strong’s smoldering billionaire David Sharpe.

According to Kidman, the creative team — including creator David E. Kelley, co-showrunner John-Henry Butterworth, and directors Jonathan Levine and Anthony Byrne — held nothing back for the flashback entry. They “take it to the next level, because Masha always does,” Kidman says. “We push every limit.”

“I was very excited by it. I worked with Nic before 10 years ago,” Strong says, referring to Before I Go To Sleep, the 2014 thriller from producer Ridley Scott co-starring himself, Kidman, and Colin Firth. He calls the opportunity to join the rest of this sprawling ensemble on their hike up to the fictional, crumbling Zauberwald estate for another round of psilocybin-assisted leaps into the void “a no-brainer, really, because the first one was great, Nic is great, and the other actors all sounded brilliant.”

Plus, “the opportunity to play a guy who’s a billionaire is always a giggle,” Strong jokes.

The character played by the London-born actor, 61, arrives at Zauberwald at the end of the first episode, shrouded in mystery and the glamour of wealth. While Sharpe appears to share the least connective tissue with the other eight “perfect strangers” — excepting his semi-estranged son, Peter (Henry Golding) — “Prague” proves that definitively untrue.

The episode reveals that Sharpe is the father of Masha’s dead daughter, Tatiana (Emílie Páclová). The pair met in 2001, when Masha is an aspiring journalist and makeup artist for a broadcast news station where David’s set to give a tone-deaf interview about “lifting the Iron Curtain and selling it for parts,” per Masha. Sparks fly, day turns to one night stand, and nine months later…

“For Masha, it’s about bringing him in particular into this equation, because of his place in her life,” Kidman says. “When you find out who he is — the father of her child — that’s very, very important. There’s a reason for it all, to the very end of this series, I won’t spoil the finale, but it’s always leading towards him. Everything is leading towards David.”

“David’s always been fascinated with Masha,” Strong says. His character embarks on the journey to Zauberwald with the ostensible motivation of reconnecting with his son, but in the pursuit of his actual desire — Masha — he gains a daughter. “She gives him this huge revelation, gives him the drugs, and he does something he really wasn’t expecting. She completely opens him up.”

Masha is coy about the fact that he’s the father of her dead daughter (“Does she know about me?” David asks. “In a way,” Masha responds), or else, in her mushroom-addled madness, the boundaries between fact and fiction, death and life are beginning to blur.

But Kidman defends her character. “It’s always with the best of intentions,” she says of Masha. “She’s not trying to harm. She has her own past, which is what [episode] five is about. She’s a difficult character, but she’s very, I think her heart is in the right place.”

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Kidman says she dug deep for the emotional episode’s big reveal. “Everything has to be real. You can’t be showing up and pretending because becomes that becomes obvious, and you don’t feel it,” she says. “You’ve got to see skin color change. You’ve got to see real tears. You’ve got to see real emotions, because that’s what this is. It’s real.”

New episodes of Nine Perfect Strangers premiere every Wednesday on Hulu.