updated 07/17/2011 AT 2:00 PM ET
•originally published 07/16/2011 AT 7:00 PM ET
So far, the contestants on Oxygen’s The Glee Project have been challenged to showcase their individuality, go over the top and be theatrical, reveal their vulnerabilities and dance to choreography.
Now comes a true test of their ability to fit into William McKinley High School – their chemistry.
Sunday’s episode, with Glee star Darren Criss returning as a guest mentor, focuses on singing duets as the show gets closer and closer to a winner, someone who will get a multi-episode arc on the third season of Glee.