Tony winner Bernadette Peters (Annie Get Your Gun,Song and Dance) and Josh Lucas (Glory Road, Poseidon) will guest-star on NBC's Will & Grace (Thursdays, 8-8:30 p.m. ET) in the series' next-to-last episode on May 11.

Peters will portray Karen's (Megan Mullally) sister while Lucas offers Jack sympathy after an embarrassing professional setback.

In the episode - "Whatever Happened to Baby Gin? -- Grace (Debra Messing) and Will (Eric McCormack) are excited about becoming parents to her baby. While Vince (guest star Bobby Cannavale) finds a beautiful brownstone that he and Will can live in, he doesn't see Grace as part of the plan. In the meantime, Grace learns some surprising personal news while Karen's sister, Ginny (Peters), who was injured during a game of Twister when the two were kids, appears back in her life. Meanwhile, Jack's show "The Badge" premieres, but his voice is dubbed by another deemed to be "more manly." Fortunately, Lucas offers him solace.

The Emmy Award-winning comedy concludes its eight-year run on Thursday, May 18 (9-10 p.m. ET).

Peters earned Tonys for Best Actress in a Musical for Annie Get Your Gun and Song and Dance (among seven total nominations). She also has starred in many film and television projects, including the features Annie,Pennies from Heaven,The Longest Yard,Alice,The Jerk and Pink Cadillac.

On television, Peters starred in the movies David,Fall from Grace,Last Best Year,Cinderella (1997 version), Bobbie's Girl,Prince Charming and the miniseries The Odyssey. She also guest-starred in Frasier and Ally McBeal (earning an Emmy Award nomination for the latter).

In addition, Peters has recorded six solo albums, earning four Grammy nominations. She also garnered two Grammys as part of two award-winning cast albums.

Lucas recently starred in the critically acclaimed box-office success Glory Road as Don Haskins, the coach in the true story of the upstart Texas Western-El Paso college basketball team that won the national championship in 1966. Lucas will also star in the upcoming Warner Brothers film, Poseidon directed by Wolfgang Peterson which will be released on May 12th.

Some of Lucas' other film credits include, the Oscar-winning A Beautiful Mind, Wonderland, Undertow, Stealth, An Unfinished Life, Empire Falls, American Psycho, The Hulk and Sweet Home Alabama.