Set your TiVo!

OPRAH WINFREY is going "all in" for the hottest acts in Vegas -- CHER and TINA TURNER!

Lady O and her crew will travel to Sin City next weekend for a once in a lifetime opportunity to see these two divas in action. She'll tape the special at The Colosseum at Caesars Palace, which will feature exclusive performances as these legends unite for a Vegas spectacular!

"The Oprah Winfrey Show: Oprah, Cher and Tina in Vegas" is scheduled to premiere Thursday, May 8.