Episodio finale di doraemon...

The animated version is completely similar but lenghtened. Nobita finds a box the shape of Doraemon in his drawer. The next day, which happens to be April Fool's day, Nobita is jeered at by Suneo and Jaian, the latter tricking him about Doraemon's return. He happily runs home and asked his mother whether Doraemon came back and finds out the truth. Nobita couldn't stand it and opens the box. Inside of it was a bottle of liquid. He hears Doraemon's voice explaining that the potion is called Uso 800 (Lies 800) it is used to make all untruths the drinker says true. Nobita uses it to play a few tricks on Jaian and Suneo, like first taking cover then say that the weather sure is good, which becomes a lie and it started to rain heavily before he said it is raining heavily and the rain stopped. Jian and Suneo was scared away after a few tricks and when Nobita mentioned what is happening. Nobita was very happy at first but quickly loses interest in the absence of Doraemon. As he walks home, due to his earlier questioning if Doraemon returned or not, his mother asked him if he could find Doraemon, he unwittingly said, in great disappointment, the truth about Doraemon never coming back, just like what Doraemon told Nobita before his departure. Since the potion was still in effect, when he arrives his room he finds Doraemon there, and they have a happy reunion, but due to the effects of the potion, all his greets and joyful words have to be spoken in the opposite way like I am so unhappy that we can never be together again.