HOLLYWOOD — For the first time in years, NBC skedmakers aren’t scratching their heads in confusion over what to do about Monday nights.

Thanks to the jolt provided by “Fear Factor” and a pair of solid dramas leading out of it that are now performing even better, primetime’s ratings leader has mastered Monday and is capable of capturing every weeknight in the key demo of adults 18-49.

NBC has some work to do on the weekends, where it continues to underperform, but for now it can relish in winning the weeknights — and that includes Monday, a night that had puzzled the Peacock even during some of its recent banner years.

When it won last season in adults 18-49, for example, NBC could fare no better than fourth on Monday. This season, according to Nielsen estimates, net’s moved up to second (a 21% year-to-year ratings gain), behind CBS.

And since “Fear Factor” moved into Monday’s 8 o’clock hour in January, NBC has assumed the night’s demo lead.

Remember the “Fresh Prince of Bel-Air?” Well, that early 1990s laffer was the last time NBC even had a pulse in Monday’s lead-off hour.

“Fear Factor” has stepped in and not only become a factor, but dominated. It even won across the board recently with a repeat — a rarity for a reality rebroadcast.

The gross-out reality skein has taken some of the ratings steam out of the timeslot’s previous demo leaders: CBS comedies “King of Queens” and “Yes, Dear” and Fox high school drama “Boston Public.”

“Fear Factor” is another example of how a potent reality performer — much more easily than a hot new drama or sitcom — can break through on a night when previously all else had failed. CBS similarly knew it could instantly become a Thursday player by moving “Survivor” there; its “Amazing Race” has also helped the net post much better scores on Wednesday opposite “The West Wing.”

“Fear’s” firepower has ignited “Third Watch,” a so-so performer its first two seasons but a solid middle piece of the lineup now. And with Fox’s “Ally McBeal” exiting, “Third Watch” enters fall as the incumbent drama in the hour.

“Third Watch” has improved NBC’s standing Mondays at 9 by as much as 28% in some demos. And that’s not including the April 29 crossover episode with “ER” that produced record ratings for the series that follows the lives of New York’s paramedics and firefighters.

And at 10 o’clock, Jill Hennessy’s coroner drama “Crossing Jordan” performs about 10% better than last year’s slot occupant (“Third Watch”), topping its hour.

Both “Third Watch” and “Crossing Jordan” skew female, but they also hold strong appeal to men, something that helps them weather the storm opposite “Monday Night Football” through December, and then improve their ratings when more men are freed up after the football season.

It’s unclear at this point how strong “Crossing Jordan” really is. While it has performed well — it’s the season’s top-rated new drama and is undefeated since ABC’s “Monday Night Football” ended its season — it has faced some pretty lightweight drama competish (CBS’ bumbling “Family Law” and ABC’s now-axed “Once and Again”).

A perception persists in some circles that NBC is just a one-night network (Thursday), but its improvement on nights like Wednesday, Friday and now Monday may slowly change that.

And when “Friends” leaves after next season, NBC will be counting even more on a balanced attack.