The 19 Most Epic Glee Performances of All Time

The only person missing from this powerhouse team is Artie (Kevin McHale)! During their tribute episode to Whitney Houston, Mercedes, Santana, Kurt, and Rachel sing one of Whitney's first hits, "How Will I Know" a cappella. The performance showed off the power of Adam Anders, Glee's executive music producer — he took a normally jazzy and upbeat song and molded it into something poignant and somber.