Hopcorn+

A man who is still mourning the death of the woman he loves, meets a man who says he created a machine that can bring anyone to a parallel world. He goes and sees the woman he loves is still alive in that world and wants to stay. But when he discovers that this world has rules that differ from his world, he wants to leave but when he goes back to where the machine is, there's a fire and the machine is destroyed and the man who built it is killed. He later meets a woman from his world who also built a machine of her own but the officials there upon seeing her thinks she's crazy because her counterpart is alive and says she doesn't know her. So he tries to help her so that they can return home.