Feel like it's too late to catch up on what's happened in Pretty Little Liars? Tonight's episode - subtitled "A Liar's Guide to Rosewood" (9 p.m. ABC Family) - recaps what has happened in the previous 71 epiodes.The new season begins a week from tonight.Elsewhere on TV ...Extreme Weight Loss (7 p.m., ABC/Ch. 4): A woman who was adopted tries to lose weight before meeting her birth mother.The Voice (7 p.m., NBC/Ch. 5): Contestants face elimination.So You Think You Can Dance (7 p.m., Fox/Ch. 13): Auditions continue.Polygamy USA (7 and 10 p.m., National Geographic): Ezra Hammon meets with the Brethren about his desire to marry Tiffany.America's Got Talent (8 p.m., NBC/Ch. 5): A new season begins, and Heidi Klum replaces Sharon Osborne on the judging panel.Brooklyn DA (9 p.m., CBS/Ch. 2): This new documentary series follows real prosecutors as they take on murder cases.Awkward (11 p.m., MTV): Jenna has a crush and a boyfriend.Kathy Griffin: Calm Down Gurrl (11:30 p.m., Bravo): Kathy performs in Santa Rosa, Calif.