Heath Ledger by J. Vespa/WireImage.com Heath Ledger by J. Vespa/WireImage.com

As police await toxicology reports that could shed light on Heath Ledger's cause of death in a way the autopsy report couldn't, new details have surfaced on how Weeds' star Mary-Kate Olsen figures into this tragic tale. As detailed in a timeline released by the NYPD, the masseuse who discovered Ledger's lifeless body first speed-dialed Olsen, a friend of Ledger's, because the employee "knows that when something goes bad, you call insiders first to see how to handle things," a source tells the New York Daily News.

As Olsen dispatched her security team to Ledger's residence, the masseuse tried to rouse the actor. When she couldn't, she phoned Olsen back to say she was alerting 911.

As previously reported, no illegal drugs were found on the premises, and a rolled-up $20 bill discovered near Ledger's body tested clean of drug residue. Six prescription medications recovered from the scene included pills to treat insomnia and anxiety, and an antihistamine.

Elsewhere, Jack Nicholson - who, like Ledger in The Dark Knight, once played the maniacal and dark Joker on the big screen - raised eyebrows on Wednesday by telling reporters in London, "Well, I warned him," when asked about Ledger's death. Though Nicholson did not elaborate, he could have been alluding to the intensity that comes with playing "a psychopathic, mass-murdering, schizophrenic clown with zero empathy," as Ledger recently characterized the role. Working off two hours of sleep a night, Ledger had said, "I couldn't stop thinking. My body was exhausted, and my mind was still going."

Related:
" News: Heath Ledger Autopsy "Inconclusive"
" Ausiello: Grieving Heath Ledger via Ennis Del Mar
" Watch video: News coverage of Ledger's shocking death
" Watch video: Clips from Ledger's films
" Photo gallery: Heath Ledger's life in pictures
" Photo gallery: Stars and friends tribute Ledger