Federline, 28, a former dancer and aspiring rapper, will play a rogue teen in an October episode of the popular high-tech cop drama.

"I play a little edgy dude," he told People magazine, adding that his wife is "very, very excited" about his new job.

"Man, she's supportive," he told People.

Critics, however, have not been so emphatic. Federline's recent performance on a music awards show of songs from his upcoming rap album, "Playing With Fire," received mixed reviews.

Spears, 24, who skyrocketed to fame in 1999 with the song "Baby One More Time" and has gone on to sell more than 60 million albums, has put her music career on hold for the past year and a half to devote more time to her family.

The couple had a son in September 2005, and Spears is currently eight months pregnant with their second child together.

Federline also has a son and a daughter from a previous relationship with actress Shar Jackson.