Doki Doki Precure: Mana is getting married!? The dress of hope that connects to the future

One day, Aida Mana received a wedding dress from her mother and grandmother that they had worn in the past. While thinking about who she would wear this besides someday herself, a mysterious man named Matthew appears, and Mana is thrown back into the past. She was happy to see her grandmother she loved and her old dog Maro, but she then realizes that Alice, Rikka and Makoto are not there because their memories have been altered. In order to save precious memories, the future, dreams and hope, Mana transforms into Cure Heart.