She has returned as a special guest star in 2006, 2007, 2008 and 2009.

He was credited as a special guest star, and first appeared on November 19, 2009.

Each episode featured one special guest star and ran for 30 to 45 minutes.

The other three 5566 members were featured as special guest stars in episode one.

In the second season, Emerson was no longer a full-time character but only a special guest star.

There is no guarantee that this special guest star will be available on other nights.

On opening night, Train was a special guest star to open the show.

Each night also featured a second set with special guest stars.

In the season 8 premiere, however, she is listed as a special guest star.

She appeared in two episodes (19 and 20) as a special guest star.