Actress Lindsay Lohan will appear as a guest star on TV musical comedy “Glee”, her spokesman said on Tuesday, in the latest step of a comeback for the once rising star whose career has been tarnished by drinking, drugs and legal troubles. Lohan's spokesman declined to give details of the episode involving the “Mean Girls” actress. But entertainment website TVLine.com said Lohan would play herself and serve as a celebrity judge when the “Glee” choir performs at a key contest toward the end of this current season. The “Glee” guest stint marks a turnaround for Lohan, who was the butt of a joke on the show in 2010 when actress Gwyneth Paltrow's school teacher character Holly Holliday delivered a sharp quip about Lohan's many stints in rehab. __