The fairy tale that blended Hollywood glamour with country twang is unraveling faster than a cheap guitar string. Nicole Kidman, 58, filed for divorce from Keith Urban, 57, on September 30 in Davidson County Circuit Court, citing “irreconcilable differences” after nearly two decades of marriage. The split, which sources say began with a private separation in early summer, has exploded into a tabloid frenzy, fueled by whispers of infidelity that could torpedo Urban’s prenuptial agreement and cost him a chunk of his estimated $75 million fortune. With Kidman’s net worth soaring at $250 million—bolstered by her Oscar-winning roles and savvy investments—insiders claim most of their shared assets, from a sprawling Nashville estate to private jets, may remain firmly in her camp if the cheating rumors hold water.

The couple, who met at a Los Angeles breakfast spot in 2005 and tied the knot in a lavish Sydney ceremony the following year, were long hailed as showbiz’s golden pair. They share daughters Sunday Rose, 17, and Faith Margaret, 14, and had built a life of red carpets and ranch retreats, with Kidman crediting Urban for grounding her amid her whirlwind career. “He’s my deep, deep love,” she gushed in a 2024 interview, just months before cracks surfaced. But behind the scenes, the grind of her film sets and his relentless tours—Urban’s High and Alive World Tour kicked off in Alabama this summer—allegedly wore thin, leaving them ships passing in the night.

Now, the real fireworks: Sources close to the duo tell RadarOnline that Urban’s “misstep”—code for an alleged affair with a “younger woman in the Nashville music business”—may have breached their ironclad prenup, signed before the 2006 wedding. “The talk is that Keith may have been unfaithful, and that could open the prenup to challenge,” one insider dished, noting the gossip mill in Music City is churning with speculation about the mystery woman’s identity. TMZ echoes the buzz, with a source from Urban’s camp admitting “all the signs point to the fact Keith is with another woman,” leaving Kidman “shocked” and “devastated.” Kidman, no stranger to high-stakes splits (her 2001 divorce from Tom Cruise netted her $80 million but custody battles), reportedly feels “betrayed,” especially after standing by Urban through his well-documented battles with addiction.

Enter the prenup’s quirky “cocaine clause,” a rumored kicker designed to reward Urban’s sobriety. According to Daily Mail reports, the agreement allegedly doles out $600,000 to $900,000 annually for staying clean from cocaine, alcohol, and other substances—potentially netting him $11 million to $17 million over 19 years. Urban, an Australian native who kicked a cocaine habit early in their romance (Kidman famously rallied him into rehab just months after their vows), has credited her support as life-saving. “If you want to see what love in action really looks like, give that a whirl,” he said at her 2024 AFI Lifetime Achievement Award gala, praising her for ignoring naysayers. But legal eagles warn that infidelity allegations could void such behavior-based clauses, which courts often view as unenforceable “moral” stipulations rather than ironclad financial ones. In Tennessee, where the filing landed, fault like adultery can influence asset splits, potentially flipping the script on their combined $325 million empire.

The marital dissolution agreement, notarized in August and attached to the filing, outlines a co-parenting plan prioritizing Kidman as the “primary residential parent” with Urban getting visitation rights. It stresses mutual respect: “The mother and father will behave with each other and each child so as to provide a loving, stable, consistent and nurturing relationship,” and bans badmouthing. Child support details remain sealed, but with Urban’s touring income (his 2025 Vegas residency grossed $40 million) and Kidman’s producing deals, expect a hefty tab. Their assets? A mix of separate fortunes—Kidman’s from blockbusters like Big Little Lies and endorsements with Chanel, Urban’s from hits like “Kiss After Kiss” and his Hit Factory Academy—plus joint holdings like a 50-acre Franklin, Tenn., spread bought for $3.5 million in 2008.

Clues to the implosion littered their summer. Urban’s awkward radio dodges of marriage praise—”Mhm, yeah”—resurfaced post-filing, as did a tense June appearance at Nashville’s FIFA Club World Cup 2025, where body language experts spotted Kidman fidgeting and Urban averting eyes. Their June 19th anniversary post, a cozy throwback from Kidman, now reads like a eulogy. Urban, meanwhile, has gone radio silent on the split, focusing on tour dates in Australia, while Kidman jetted to Paris Fashion Week with daughters in tow, debuting a bold hair refresh that screamed reinvention.

X (formerly Twitter) is ablaze with speculation, from divorce party rumors for Kidman—courtesy of A-list gal pals—to fans dubbing their teen daughter a “nepo baby” after her Dior runway strut. One viral thread blames Kidman’s “spicy” roles in back-to-back films as the “nymphomaniac cougar” for straining things, while others recirculate her six-word zinger about ex Cruise: “I didn’t want to stay married to him.” In a fresh interview, Kidman opened up about “devastating” lows: “If you move gently and slowly… it does pass,” a veiled nod to the heartbreak.

Urban’s camp pushes back on the cheater narrative, with a rep telling Fox News the rumors are “hurtful fiction,” but Nashville insiders aren’t buying it: “Everyone wants to know who, but so far, that’s a mystery.” If proven, the affair could slash Urban’s take, forcing a renegotiation where Kidman’s clout tips the scales. Their story, once a beacon of blended-family bliss (Kidman’s older kids from Cruise, Bella and Connor, even walked her down the aisle in 2006), now underscores Hollywood’s brutal math: Love fades, but lawyers endure.

As proceedings drag into 2026, expect more leaks—sobriety audits, asset audits, the works. For now, Kidman’s channeling the pain into work, eyeing a Expats Season 2 comeback, while Urban strums through sold-out shows, his setlist heavy on heartbreak anthems. In a town built on ballads of betrayal, this one’s got Grammy potential. But at what cost to the empire? Stay tuned—Nashville’s just warming up.