Mia (Anne Hathaway) ya está preparada para ser princesa de Genovia. Sin embargo, nada más instalarse en el Palacio Real con su bella y sabia abuela, la Reina Clarisse (Julie Andrews), se entera de que tendrá que prepararse inmediatamente para ser reina. Pero, entonces, tendrá que afrontar un peliagudo problema: en Genovia hay una ley que establece que las princesas tienen que casarse antes de ser coronadas; así que Mia tendrá que soportar un desfile de pretendientes cuya única aspiración es ocupar el trono.
Felix's daughter Edna is getting married, and his wife Gloria throws him out of the house for a few days, so that she can plan the wedding herself, without him getting in the way. Felix temporarily moves in with Oscar, who is still living in the same apartment from the TV show. Due to throat cancer, Oscar had to have one of his vocal cords removed, and he can only speak in a raspy whisper. Meanwhile, plans for the wedding are going on, and things get complicated when Felix finds out that Edna's fiancé has been divorced twice.
