The live action Doraemon advertisement, from car company Toyota continues, as AKB48's Atsuko Maeda enters the scene as Jaiko, Gian's younger sister. The fourth ad is entitled “Nobita's What-If World.”
Atsuko Maeda herself was a fan of the earlier ads and said that she never imagined in her wildest dreams that she would become part of the Doraemon family.
The new "Nobita's What-If World" ad begins with Nobita giving up in defeat after failing the driver's license test. He wanted the license so he can take Shizuka on a car date, so he muses what it would be like if he had succeeded. Doraemon is munching on his favorite snack, dorayaki when he brings out his Moshimo Box (What-If Box).
With the box, Doraemon shows Nobita the "what-if world" where he did earn the license. A compact hybrid car appears before Nobia in the "what-if world," but so does a mysterious woman who turns out to be Jaiko.