NBC’s “The Singing Bee” cooled off quite a bit in its second outing, though it remains the summer’s hottest new show.

“Bee” averaged a 3.6 adults 18-49 rating last night, according to Nielsen overnights, down 29 percent from last week’s 5.1 rating for its debut.

“Bee” also dipped in total viewers, from 13.3 million total viewers last week to 10.8 million last night.

Nonetheless, “Bee” was the top show last night in 18-49s. It built on its “America’s Got Talent” lead-in for the second straight week, a good sign for NBC, and dominated its closest timeslot competitor at 9:30 p.m., CBS’s “Big Brother,” by 22 percent.

Last week “Bee” became the highest-rated summer show debut in five years, so the dropoff wasn’t all that surprising; most new shows don’t sustain their debuts. The karaoke reality show got a big boost from advertising on “Talent” and likely curiosity about the show, hosted by popular former ‘N Sync singer Joey Fatone.

But it may also have been hurt by the debut of Fox’s similarly themed “Don’t Forget the Lyrics,” which aired two episodes to solid ratings last week.

Still, even if “Bee” slips another few tenths, it will be summer’s most successful new program.

Also last night, ABC’s “Just for Laughs” got off to a good start, growing 11 percent from its first half hour to its second in its 8 p.m. debut. It averaged a 2.8 in 18-49s.

“Talent” and “Bee” boosted NBC to first for the night among 18-49s with a 3.1 average overnight rating and a 10 share. ABC was second at 2.4/7, CBS third at 1.9/6, Univision and Fox tied for fourth at 1.5/5 and CW sixth at 0.6/2.
 
NBC actually led each hour of the night, beginning with a 3.0 at 8 p.m. for its first hour of “Talent.” ABC was second with a 2.8 for “Laughs,” CBS third with a 1.5 for a repeat of “NCIS” and Univision fourth with a 1.2 for “Amar sin Limites.” Fox was fifth with a 0.9 for “On the Lot” and CW sixth with a 0.7 for a repeat of “Gilmore Girls.”
 
At 9 p.m. NBC led again with a 3.5 average for the last half hour of “Talent” (3.4) and a new episode of “Bee” (3.6), followed by CBS with a 2.7 for “Brother.” Fox moved to third that hour with a 2.1 for a repeat of “House,” with ABC fourth with a 1.9 for “Shaq’s Big Challenge,” Univision fifth with a 1.8 for “Destilando Amor” and CW sixth with a 0.6 for a repeat of “Beauty and the Geek.”
 
At 10 p.m. NBC finished its nightly sweep with a 2.8 for a repeat of “Law & Order: Special Victims Unit,” with ABC second with a 2.5 for “Primetime: Family Secrets.” Univision was third with a 1.6 for “Ver para Creer” and CBS fourth with a 1.5 for “Pirate Master.”
 
NBC also finished first for the night among households, averaging a 6.5 overnight rating and an 11 share. ABC was second at 4.4/8, CBS third at 4.2/7, Fox fourth at 2.7/5, Univision fifth at 1.8/3 and CW sixth at 1.0/2.