The New Directions should start worrying, like, now. Longtime rival and former Vocal Adrenaline star-turned-director Jesse St. James is set to return for Glee's series finale, E! News reports.

Star Lea Michele tweeted a picture on Thursday of her and her real-life BFF Jonathan Groff, who plays Jesse, on stage in the McKinley High auditorium.

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It's unclear just how Jesse, who also dated Rachel back in Season 1 - how else was Glee going to get in a cover of "Jesse's Girl"? - will return to the show after a significant amount of time away. Groff last appeared in the penultimate episode of Season 3, in which his Vocal Adrenaline group was no match for the New Directions, who won Nationals. We'd love to get his take on Will taking over as director for Vocal Adrenaline.

Groff currently stars on HBO's comedy Looking.

Glee airs Fridays at 9/8c on Fox. The series finale is set for March 20.

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