Hot off the presses—a brand new pic from next Tuesday’s Glee episode guest starring Britney Spears. Brittany (Heather Morris) attempts to charm a snake in her rendition of Spears’s  “Slave 4U.” We can’t wait ’til next week! Till then, watch Santana and Brittany tease their dentist (John Stamos) with a sultry performance of “Me Against the Music” after the jump.