Janet Jackson (8 p.m., LIfetime / A&E) - This new four-hour documentary marks the 40th anniversary of Janet Jackson’s first album, “Janet Jackson” in 1982. The filmmakers had full, unprecedented access to the singer, resulting in an intimate, honest and unfiltered look at her untold story. Producers filmed the documentary for over three years and had exclusive access to archival footage and never-before-seen home videos, along with star-studded interviews. In addition to her career, the film will look at Jackson’s private life for the very first time, and reveals some of her most intimate moments caught on camera. This new documentary airs across two networks on two nights, with the second part airing on Friday. In tonight’s first part, Janet’s father, Joe Jackson, puts her to work in the family show at the age of 7. Her father never asked if she wanted to be a performer, so it’s up to Janet to find her own path.