Britney Spears: She used to make a spectacle of herself. Now she wears them. Why put on Drew Carey’s glasses? To add a little gravitas to her new role as a judge/mentor on the second season of “The X Factor” (7 p.m., Fox).

As we all know, the show’s first season in the U.S. was a bit of a nonstarter. Simon Cowell and Fox hoped that this new version of the hit U.K. singing competition would create a second Death Star, an unassailable ratings giant to complement “American Idol.” That didn’t happen. If anything, “X,” along with “The Voice” and “America’s Got Talent,” combined to saturate the airwaves and create a sense of talent show exhaustion among viewers that contributed to diminishing returns for “Idol.”

So this year “X” returns with two new judges. On one level, choosing Spears and Demi Lovato makes a lot of sense. The audience for these showcases seems to be composed of teenage girls consumed with dreams of becoming big stars. And both judges were celebrities well before their 20th birthday.

Although Spears and Lovato stand in nicely as figures of tween wish fulfillment, they are also essentially competing for the role pioneered by Paula Abdul — that of the flirtatious music industry has-been clutching desperately to her second 15 minutes of fame. And they’re both a little too young for that role.

In the 10-minute reel made available for review, Spears does little to stand out. She wears black plastic glasses nicely and verges on happy tears when a 13-year-old ingenue belts out “Feeling Good,” made famous by Nina Simone. Watching a kid barely out of grade school interpret a number by a world-weary diva is part of what makes this karaoke showcase so peculiar and occasionally morbid.

Bottom line: Glasses won’t make Britney Spears any smarter, and two new judges won’t save “X Factor” from its own has-been status.

Tonight’s other highlights

• Six acts get their final crack at fame on “America’s Got Talent” (8 p.m., NBC).

• A patient takes Hank far from the Hamptons on “Royal Pains” (8 p.m., USA).

• “Inside the NFL” (8 p.m., Showtime) takes a glance around the gridiron.

• Shrill stereotypes sink the gay parenting/surrogacy sitcom “The New Normal” (9:30 p.m., NBC).

• A father and son scour the globe for vintage weapons on “Family Guns” (9 p.m., National Geographic).