Elliot D'Souza, Chief Financial Officer for a high-powered publishing company, is working out in his private gym alone when suddenly the weight of his barbell overwhelms him and it comes crashing down violently on his throat. He's killed instantly, choked to death by his own workout equipment. Is it just an unusual accident, or something more sinister?
Elliot's secretary, Miss Luden, is certain that Dexter Larsen, the infamous publisher of the gentlemen's magazine Sapphire, somehow orchestrated her boss' death. As it turns out, Elliot was planning to close the doors of the infamous swinging party palace, the Sapphire Mansion. Not satisfied by the results of the police investigation, Miss Luden asks Monk and Sharona to take the case.
Monk and Sharona question Dex about the murder, and Monk immediately notes several inconsistencies in his story. Dex said he called Elliot from his cell phone, and claims he was in bed with his girlfriend Amber at the time - wouldn't he have just used the phone on the nightstand? Also, the earring Dex claims Amber left in the bed on the night in question is meant for pierced ears, and Amber's ears are clearly pierce-free. Finally, Monk wonders why Larsen insisted that his celebrity pal Danny Bonaduce stay the night at the mansion to avoid driving home drunk on the night of the murder - especially since Danny himself insists he was sober that night. Dex is able to sidestep Monk's questions, but Monk remains suspicious, and continues to dig deeper.
Fearing that Monk is getting too close to the truth, Dex produces his ace in the hole: a series of nude photos of Sharona, taken back when she was a single mother struggling to make ends meet. Dex threatens to publish the photos if Adrian doesn't agree to drop the case. As instructed, Monk halts his investigation immediately, and informs Captain Stottlemeyer that he feels Elliot D'Souza's death was an unfortunate accident.
Wondering why Monk would drop a case he was so close to solving, Sharona pressures him for answers. Reluctantly, Monk tells an embarrassed Sharona about the photos and Dex's threat to publish them. Desperate to retrieve the nude pictures, they decide to crash one of Dex's infamous parties, where Monk meets Noelle Winters, one of Dex's Sapphire Girls from the 80's. Noelle has nothing but kind words for Dex - after all, he recently purchased an apartment for her. Meanwhile, Sharona finds Dex and demands the photos, but Dex smugly refuses to turn them over to her. Sharona tells Monk to "nail the creep."
With Sharona's blessing, Monk finally uncovers the truth. What Monk learns is that the apartment Dex bought for Noelle was directly beneath Elliot D'Souza's. On the night of the murder, Dex used Danny Bonaduce's car to drive to Noelle's place, where he used an incredibly powerful electromagnet of his own design to murder Elliot by pulling his barbell down on top of him.
To the naked eye, Dex's plan was brilliant: Elliot's murder looked like a weightlifting accident. He thought of everything, planned for every contingency. Except he overlooked one crucial element: Adrian Monk.