Osamu Tezuka is going to a 21st Century new year's party with all the characters he made. One thing leads to another and he ends up missing! It's up to his most popular characters to find out what happened to him and get him back safely before the rest of the guests show up.
Nothing is impossible for Doraemon's magic pocket, much less when it comes to using their inventions to live the most amazing adventures. Is there a place where no man has gone before? The robot cat magic door leads to our friends at the center of Africa, just until Smokers Forest, a forest covered with a thick fog that prevents satellites take pictures. Nobita and his friends decide that if there is so much to discover, is certainly there.
The plot of Marine Express can be described in two parts. The first part focuses on the people boarding the train and the problems they encounter on it. The second part takes place after the train has stopped at its half-way point, an island that used to be home to an ancient civilization millennia ago and has its fair share of secrets.