TV Ratings: Brian Williams' 'Rock Center' Starts Soft on Night of Declines, 'Castle' Improves 21%

37 REP Rock Center Brian Williams Harry Smith H
Patrick Kramer/NBC

Brian Williams (left) and Harry Smith on the set.

It was gloomy on Halloween night, with television usage down 8 percent from last year and about 10 percent lower than the previous week. On a night of declines -- and the debut of NBC newsman Brian Williams' primetime effort Rock Center -- there was a bright spot that bucked the downward trend: ABC's veteran "whodunit" drama Castle.

Expectations were modest for Rock Center (4.1 million total viewers, 1.0 rating in adults 18-49 demographic). "We’re not doing this as a ratings play. We’re not kidding ourselves, we know it’s going to take some time to get established," said NBC News president Steve Capus during a conference call with reporters Oct. 24. Compared to The Playboy Club's debut (which it replaced), Rock Center was down a hefty 38 percent in the demo for the 10 p.m. time period. Its lead-in, The Sing-Off (4.4 million, 1.4), posted its lowest-rated telecast to date.

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ABC's Castle was the only series on Monday to improve drastically for the holiday. The hostage crisis episode drew 12.9 million viewers and a 2.9 rating opposite Rock Center and Hawaii Five-0, tying the latter in the demo. Notably, Castle topped Dancing With the Stars (16.3 million, 2.8), which declined 13 percent from last week (8-10 p.m.) to its lowest performance show to date. An airing of Scared Shrekless (8.7 million, 1.7) led off the night for ABC and was down 35 percent from last year's debut on rival network NBC.

The return of Terra Nova and House after time off the air due to the baseball playoffs didn't prove splashy. Terra Nova (6.4 million, 2.1) saw a 25 percent decrease from its last original airing two weeks ago, while House (6.5 million, 2.5) sank 19 percent in the same timeframe.

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CBS won the night in the advertiser-coveted demo, averaging a 3.8 rating in primetime, even while its lineup was under the Halloween spell. 2 Broke Girls (11.1 million, 4.2), Two and a Half Men (13.8 million, 4.7) and Mike & Molly (11.5 million, 3.8) all posted lows thus far this season, while How I Met Your Mother (10.7 million, 4.1) and Hawaii Five-0 (10.3 million, 2.9) dropped 5 percent and 6 percent, respectively.

The CW aired repeats of Ringer (1 million, 0.3; 867K, 0.3).

CBS -- 3.8          
· How I Met Your Mother: 10.7 million, 4.1      
· 2 Broke Girls: 11.1 million, 4.2
· Two and a Half Men: 13.8 million, 4.7     
· Mike & Molly: 11.5 million, 3.8
· Hawaii Five-0: 10.3 million, 2.9
ABC -- 2.7          
· Scared Shrekless: 8.7 million, 1.7
· Dancing With the Stars: 17 million, 3.1          
· Castle: 12.9 million, 2.9
Fox -- 2.3
· Terra Nova: 6.4 million, 2.1          
· House: 6.5 million, 2.5

NBC -- 1.2           
· The Sing-Off: 4.4 million, 1.4         
· Rock Center With Brian Williams (P): 4.1 million, 1.0 

The CW -- 0.3          
· Ringer (R): 1 million, 0.3        
· Ringer (R): 867,000, 0.3