"Will & Grace" (8:30 p.m. Thursday, Sept. 16, NBC) is getting back its Grace.

Actress Debra Messing returns from her maternity leave for the comedy's season opener, but Grace isn't happy about it. She's dealing with her husband's affair.

"This is going to be a year of tremendous growth for Grace," says executive producer Alex Herschlag. "We're going to be dealing with her relationship not working out."

Other developments coming this season:

- Will (Eric McCormick) celebrates a new love with a man he met last season (Bobby Cannavale) as Grace spirals because of her broken marriage.

- Jack (Sean Hayes) ends his touring with JLo and considers the possibilities of working with Janet Jackson (the two superstar singers have cameos this season).

But, alas, Jack does not continue the dance. He gets a new job as an executive for a new television network aimed at gays.

"It will ground my character more," Hayes says. "It will give him something more to grab onto."

- Harry Connick Jr. will return for at least one episode as Grace's estranged husband.

- Karen (Megan Mullally) will be newly single, too. Her marriage ends before her wedding reception does.