Beast Wars II refers to the 1998 Japanese Transformers television animated series, and the movie and toyline that resulted from it. The series was preceded by Beast Wars, and was followed by Beast Wars Neo. The series has a much lighter tone and is aimed more towards children, whereas the more accessible Beast Wars was intended for a wider age range. The series also uses conventional animation rather than CGI like Beast Wars: Transformers. With the exceptions of the faction leaders, all of the characters within the series are either re-molds or re-colors of earlier Beast Wars figures or Generation 2/Machine Wars figures. In addition to the 43 episodes, there is also a 50-minute movie, Beast Wars II: Lio Convoy's Close Call!, which takes place sometime between episodes 32 and 38.

A spaceship carrying a Dimentional Warp Gate crashes on Planet Gaea. Galvatron tricks Lio Junior into handing over the control of the gate. With the power to cross time and space, Galvatron intends to bring Megatron to Gaea. But Gigastorm mistakenly brings the behemoth Majin Zarak instead. The Maximals are overpowered by this Predacon giant, so Magnaboss using the gate to call in Optimus Primal...