The Human Centipede (First Sequence) is a 2009 Dutch independent body horror film written, directed and co-produced by Tom Six. The film concerns a deranged German surgeon who kidnaps three tourists and conjoins them surgically, mouth to anus, forming the eponymous "human centipede". It stars Dieter Laser as Josef Heiter, the creator of the centipede; and Ashley C. Williams, Ashlynn Yennie, and Akihiro Kitamura as Heiter's victims.

According to Six, the concept arose from a joke he had made with friends about punishing a child molester by stitching his mouth to the anus of a "fat truck driver". Other sources of inspiration were Nazi medical experiments performed during World War II, such as those performed by Josef Mengele at the Auschwitz concentration camp. When approaching investors to fund the project, Six did not mention the premise of the film for fear of putting off potential backers; financiers did not discover the full nature of the film until completion.

The film held its premiere at the London FrightFest Film Festival on 30 August 2009. It received a limited theatrical release in the United States on 30 April 2010. Despite a mixed critical reception, the film won several accolades at international film festivals. Two sequels that were also written and directed by Six—Full Sequence and Final Sequence—were released in 2011 and 2015, respectively. The entire trilogy was combined into a single film in 2016, titled Complete Sequence, which Six described as a "movie centipede" due to each Sequence leading into its successor while simultaneously working as a separate standalone film.