The group sing follows with the Motown theme from last night with "Ain't No Mountain High Enough," though there seem to be a few technical issues (Lauren and Casey's part, when they're in the stands, is quite quiet in the middle). Then a door opens, and there's Stevie Wonder! He sings "Signed Sealed Delivered" with the Top 11, and I think it was a bit of surprise for the judges because they look pretty stunned. Love it! Speaking of surprises, Stevie makes Steven Tyler stand up and they start singing "Happy Birthday," presenting him with a painting and a cake.