Jay Leno Jay Leno

NBC's brief, disastrous experiment with bringing Jay Leno to prime time ends tonight at 10/9c, as The Jay Leno Show airs its last episode. Leno returns March 1 to The Tonight Show, which he hosted for 17 years before ceding it to Conan O'Brien for seven months.

Guests for the final Jay Leno Show will be Ashton Kutcher and Bob Costas.

Many fans of O'Brien, who left NBC as a result of its late-night shakeup, vowed never to watch the re-Leno-gized Tonight Show. But Leno has already scored public relations points with a Super Bowl ad that found him watching the game with Oprah Winfrey and longtime rival David Letterman.