Hollywood actress Jennifer Aniston, who mainly focused on acting in big screen productions since "Friends" wrapped up four years ago, will be returning to NBC for a must-see appearance in an episode of Grammy winning comedy "30 Rock," a solid source familiar with the deal confirmed.

However, there are no immediate details on Aniston's role or the episode's airdate.

"She is shooting now," a source was quoted by E!Online as saying. "We are not giving any specifics on her character."

Given the Saturday Night Live-esque nature of the series, Aniston could be playing either herself or a scripted character.

The 39-year-old actress is not the only "Friends" alum to star in the series, —David Schwimmer also had a role as Greenzo during the environmental episode. Other stars who have guested on the series include Andy Richter, Paul Reubens, Edie Falco, Will Arnett, Isabella Rossellini, Steve Buscemi, Tim Conway, Carrie Fisher and Elaine Stritch.

Aniston made an appearance in one episode of the FX series "Dirt", a show about celebrity journalism starring Aniston’s "Friends"-mate — and real life pal — Courteney Cox, in 2007.

Starring Tina Fey and Alec Baldwin, "30 Rock," which is a behind-the-scenes spoof of a TV network, begins its third season in October.

Aniston, who most recently made headlines by dating rocker John Mayer, can next be seen in a new comedy titled "Management," where she plays a traveling art saleswoman. The movie premieres at the Toronto Film Festival on Sept. 7.