"Mega Shark" is a fictional giant shark featured in the 2009 film titled "Mega Shark vs. Giant Octopus." The movie is known for its low-budget production and over-the-top special effects, which have garnered a cult following. The plot revolves around a massive shark that threatens humanity, leading to a battle against a giant octopus. The film stars Deborah Gibson and Vic Chao, who play scientists trying to stop the monstrous creatures. "Mega Shark" is part of a genre often referred to as "mockbusters," which are films that mimic popular blockbusters but are produced with lower budgets and often feature absurd storylines.