Transformers: Revenge of the Fallen takes place 2 years after Transformers. The Autobots are secretly working with the Government to destroy the last remaining Decepticons. But the Decepticons regroup, bring Megatron back to life and deal a HUGE blow to the Autobots.
Special effects are an important part of the movie business. From May to September each year, movie studios big and small try to blow audiences with their biggest budget releases of the year, and the majority of these are centered on the special effects.