While promoting Country Strong, Gwyneth Paltrow revealed to Access Hollywood that she would be reprising her Glee role of substitute teacher, Holly Holiday, in a future episode. We still don't know when she'll tape the episode or when it will be aired, but seeing as the general public seems to think Mr. Schuester is wearing thin these days, maybe he'll finally lose his shit over Emma and the Glee club will have to stage an intervention (led by Holly) to get him back on track and back to inspiring the students to forsake studying the Constitution in honor of recreating Lady Gaga's greatest hits.
Source: Access Hollywood