Kate Hudson finds Lea Michele a ''nightmare'' on the 'Glee' set.

The 'Almost Famous' actress is shooting a six-episode arc on the show and while she loves hanging out with the rest of the cast, insiders claim she finds Lea trying.

A source told Us Weekly: ''Kate says Lea is a nightmare. Once, during a technical delay, Lea snapped her fingers and said, 'Let's go. I have plans!'

''Kate's keeping her distance.''

However, Lea insists she and Kate have a great relationship.

A representative said: ''Lea has had a great time with Kate.''

Other guest stars this season include Sarah Jessica Parker after network Fox vowed the show - which experienced a drop in ratings last season - is ''poised for a creative renaissance'' when it returns in a new Thursday night slot later in the year.

Fox's entertainment president Kevin Reilly explained 'Glee' will become a ''show within a show'' following some of the McKinley High graduates as they attend a New York performing arts school, as well as introducing ''some new faces'' at the main Ohio educational establishment.