NBC’s ”Fear Factor,” airing for the first time in five years, opened well Monday, logging one of the net’s best series scores of the season. CBS still won the night, as ”2 Broke Girls” looked very good in its first try leading off the lineup and ”Two and a Half Men” remained the night’s top program.

According to preliminary national estimates from Nielsen, the Joe Rogan-hosted ”Fear Factor” averaged a 3.2/8 share in adults 18-49 and 8.7 million viewers overall in a special preview episode at 8 p.m. and then delivered potent second-place numbers in its regular 9 p.m. slot (3.5/8 in 18-49, 8.5 million viewers overall). The 3.5 is the best for a regular NBC program in the timeslot since the series premiere of ”The Event” nearly 15 months ago, and is more than double the weak 1.5 that competition series ”The Sing Off” has averaged in same-night results for the first 12 weeks of this season. It’s also the second best score for any NBC entertainment series this fall, behind the season premiere of ”The Office” (3.9).

At 10 p.m., newsmag ”Rock Center” took advantage of its stronger lead-in to post one of its best scores to date (1.1/3 in 18-49, 4.0 million viewers overall). Beginning next week, new gameshow ”Who’s Still Standing” will kick off the night for NBC.

CBS opened with a special 8 p.m. episode of rookie hit ”2 Broke Girls” (4.1/11 in 18-49, 12.5 million viewers overall), easily winning its time period and down just 1 share from the previous week’s demo score for veteran timeslot occupant ”How I Met Your Mother.” It was followed by a repeat of ”Broke Girls” in its regular slot (3.3/8 in 18-49, 10.2 million viewers overall) and original episodes of ”Two and a Half Men” (4.6/11 in 18-49, 14.7 million viewers overall) and ”Mike and Molly” (3.9/9 in 18-49, 12.8 million viewers overall); ”Men,” with a softer lead-in this week, hit a season low but still led its timeslot , as did ”Mike and Molly.” And at 10, ”Hawaii Five-0” was easily the No. 1 broadcaster (2.8/7 in 18-49, 10.9 million viewers overall).

CBS led the broadcast pack for the night in 18-49 (3.6/9), 25-54 (4.7/11) and total viewers (12 million).

Elsewhere, Fox’s ”Terra Nova” (2.1/6 in 18-49, 7.0 million viewers overall) was in line with its most recent episode and continues to perform modestly. A repeat of ”House” aired at 9 (1.4/3 in 18-49, 4.4 million viewers overall).

ABC had a quiet night with the special ”I Want a Dog for Christmas, Charlie Brown” (1.4/4 in 18-49, 5.3 million viewers overall), gameshow ”You Deserve It” (0.9/2 in 18-49, 3.4 million viewers overall) and a repeat of drama ”Castle” (1.0/2 in 18-49, 4.2 million viewers overall).

And CW aired two repeats of ”Hart of Dixie,” averaging a 0.5/1 in 18-49 and 1.3 million viewers overall for the night.

Preliminary 18-49 averages for the night: CBS, 3.6/9; NBC, 2.6/7; Fox, 1.8/4; Univision, 1.4/4; ABC, 1.1/3; CW, 0.5/1.

In total viewers: CBS, 12.0 million; NBC, 7.1 million; Fox, 5.7 million; ABC, 4.3 million; Univision, 3.3 million; CW, 1.4 million.