Nothing spells camp and nostalgia like Mamma Mia!, while the musical sub-genre isn’t for everyone, the fans of the film and its sequel are always willing to see a third movie in the franchise starring Meryl Streep and Amanda Seyfried. While Hollywood is in the phase where everything old is reliable and worthy for a sequel, the murmurs around a possible Mamma Mia 3are going strong. Finally, Seyfried shed some light on why the threequel is getting stalled.