Forte - featuring U-M grad and Saline resident Sean Panikkar (center) - will compete in the semifinals on Tuesday, August 27 at 9 p.m. on NBC.NBCSaline native and U-M grad Sean Panikkar was under lock and key on Tuesday, as he waited to compete with the male opera trio Forte in the semifinals of NBC's "America's Got Talent." (The performance episode airs August 27 at 9 p.m., after which viewers can vote for their favorite contestants; the results show airs Wednesday, August 28 at 9 p.m.) "We aren't allowed to leave the Radio City holding room, which is in the basement, so I have no cell signal," Panikkar wrote in an email.