ET is on location in Greece with the stars of this summer's hottest movie musical -- 'Mamma Mia!' -- and our Jann Carl is giving you a behind-the-scenes glimpse of all the excitement in her new video blog!

Starting Monday, ET will broadcast from Greece, bringing you all the 'Mamma Mia!' movie magic with interviews with Meryl Streep, Pierce Brosnan, Amanda Seyfried and more -- all from the romantic Greek Isles where the film was shot!