I’m worried about NBC. Like a mixed-up teenager who won’t come out of his room, the once proud network seems to want to disappear. Or just give up. I’m almost expecting to find the NBC Peacock on the back of milk cartons.

The network had a pretty healthy fall. Much of that was due to “Sunday Night Football” and the popularity of talent contest “The Voice.” Now that those shows are over, the pickings on NBC are slim. It did broadcast the finale of critical darling “30 Rock” and brought back the ambitious, if frequently ridiculous, “Smash.” But when you take away reality fluff, phony “news” magazines and repeats, NBC is down to about 2 1/2 nights of entertainment broadcasting.

The week has seven nights.

On Friday, the network aired a two-hour “Dateline NBC,” followed by “Rock Center With Brian Williams.”

Saturday brings us “American Ninja Warrior” (7 p.m.), a sports competition series better suited to cheap syndication, followed by a repeat of “Chicago Fire” (8 p.m.) and a rare repeat of “Saturday Night Live” (9 p.m.) in prime time.

Has anybody told NBC that this is February? As in sweeps month — the period when the Nielsen folks measure ratings? Sweeps used to bring big, ambitious projects: miniseries, specials, movies, cliffhangers, weddings. Seriously, a repeat of a remake of Betty White’s birthday party? That would be funny if weren’t so sad.

Not everything on CBS, ABC or Fox is stellar. But you still get the sense that those networks are at least showing up. Not NBC. What would you do with an employee who came to work two days a week?

NBC, I’m worried about you.

Saturday’s other highlights

• The kids wax romantic in the 1994 special “Be My Valentine, Charlie Brown” (7 p.m., ABC).

• Hardy and the FBI anticipate the new disciple’s next move on “The Following” (8 p.m., Fox).

• Steve Carell, Jason Segel, Russell Brand, Julie Andrews and Will Arnett voice the 2010 animated comedy “Despicable Me” (8 p.m., ABC).

• Urban renewal reveals a murder site on “Ripper Street” (8 p.m., BBC America).

• Helen Mirren, Paul Rudd, Leslie Mann and Little Mix appear on “The Graham Norton Show” (9:15 p.m., BBC America).

• Justin Bieber hosts and performs on “Saturday Night Live” (10:30 p.m., NBC).

— Copyright 2012 United Feature Syndicate, distributed by Universal Uclick.