The all-new special TMZ Investigates: Lisa Marie Presley: Unending Tragedy reveals information about the cause of death of Elvis's only child.

This TMZ investigation will dive deep into the current unsettled conflicts revolving around Lisa Marie Presley's unforeseen passing, including never-before-heard details about the money Lisa left behind and who will inherit the fortune.

As for who will gain custody of Lisa's 14-year-old twins, TMZ Investigates has the details. In regard to which family members continue a relationship with the twins, TMZ knows a conflict is brewing. The special also will bring to light the truths behind tragedies Lisa endured during her life, such as the demise of her marriage to the "King of Pop," Michael Jackson, in which TMZ exclusively speaks to close friends and family who state their marriage was real, and truly heartbreaking for both parties when they decided to divorce. The special premieres Monday, Jan. 30 (8:00-9:00PM ET/PT) on FOX.

TMZ Investigates: Lisa Marie Presley: Unending Tragedy is executive-produced by Harvey Levin, Don Nash, Charles Latibeaudiere, Ryan Regan, Jess Fusco with co-executive producer Susan Favre. Viewers can watch with On Demand, FOX NOW, Hulu and FOX Entertainment's streaming platform, Tubi. On Demand episodes are available for customers of Cox Contour TV, DIRECTV, DIRECTV Stream, DISH, fuboTV, Hulu + Live TV, Optimum, Spectrum, Verizon FiOS, XFINITY, YouTube TV and many more.