The Teen Titans encounter a new villain in their home town of Jump City, an advanced ninja named Saico-Tek. Capturing him means following a trail of clues to discover Saico's true chief commander: Brushogun, which eventually leads them to Tokyo, Japan. Once there, the team battles a beast that appears to be working for Brushogun, as well. Nearing defeat by the monster, the Titans meet up with Daizo Uehara, the Commander of the Tokyo Troopers armed forces. Assuring them that all will handled in terms of apprehending Brushogun, the Teen Titans set out to enjoy Tokyo as a vacation, while they are still there, although Robin, as overworking and serious minded as usual, is reluctant to join them. However, he soon forgets work for a little while, and enjoys some romantic moments with Starfire, which is featured as a predominant subplot throughout the film.
Meanwhile, each individual member of the team explores Japan as they see fitting: Cyborg wandering around town for food, Beast Boy on the never ending quest for chicks, and Raven for some reading material, which is apparently impossible, even after the ability of reading six languages. Little known to them, they have each been followed by mysterious shadows, and are soon ambushed one by one. Robin encounters Saico-Tek once again, and engages in a struggle on the rooftops. In a fit of rage, he is shown to have killed Saico, and is promptly arrested by the Tokyo Troopers.
After spending time in prison, then in a transport vehicle, a mysterious explosive disc frees Robin, who is now a wanted man. With all of the Troopers searching for him, he dons a new disguise, stolen from a would-be mugger in an alley way. This little get up is no match for Daizo, as him and the rest of his combat squad soon locate Robin, and a high speed pursuit through Tokyo ensues. After being surrounded and seeing no way out, Robin is forced to surrender, when all of a sudden, his rescue angel by the name of Starfire swoops in and flies them off to safety.
Now in a secluded temple, Robin and Starfire share some soft spoken words, and the two love birds attempt another go at their first kiss. This is stopped short, again, by the forms of Beast Boy. Reunited once again, the team learns through Raven's discoveries, the legacy of Brushogun. The Troopers soon interrupt their get together, and once again, the Titans are on the run. Finally shaking them off of their trail, the team winds up in a final battle against Brushogun, and ultimately defeats him. Robin and Starfire soon share their long awaited kiss, and the couple shows off their new relationship to the public at the Titan's honorary ceremony. Each are awarded medals, and the Teen Titans are declared heroes.