NBC thought it might finally have a hit on its hands with John Grisham's "The Firm." But instead, it might have yet another dud.

"The Firm" premiered Sunday on a special night to a 4.0 rating/6 share average, according to Fast National overnight ratings from The Nielsen Co. Probably worse news for the show is that it actually lost viewers -- about 12 percent of its audience -- between the first and second hour. That meant at least a tenth of the audience didn't bother sticking around for the conclusion.

If there was any good news for NBC, then it would be the fact that if it were compared to numbers compiled through the end of last year, "The Firm" would be NBC's No. 4 show behind "Law & Order: Special Victims Unit," "Harry's Law" and "Fear Factor." It also would be in the top 50 overall -- not exactly a stellar place, but not bad for NBC whose highest-ranking show is "SVU" at No. 36.

However, not much else could be said positively for "The Firm." Its first hour was 9 percent lower than what NBC did in the timeslot last year. At 10, the audience was actually down 30 percent.

Among new show premieres for NBC, it's tied for fifth with "Whitney," which also debuted with a 4.0/6. "Up All Night" (6.7/11), "Prime Suspect" (4.1/7), "Grimm" (4.1/7) and "Free Agents" (4.0/7) all finished ahead of it. "The Firm" did beat the premieres of "Who's Still Standing" (3.4/6) and "Playboy Club" (3.4/5).

"The Firm," an update on the Grisham novel as well as the 1993 movie, stars Josh Lucas as Mitch McDeere and Molly Parker as his wife, Abby McDeere. It also stars Tricia Helfer, Juliette Lewis, Shaun Majumder and Callum Keith Rennie.

It will move to its new timeslot this week of Thursdays at 10 p.m. ET, replacing "Prime Suspect," which averaged a 3.2/5 there in the first half of the season.