Kang and Kodos are a duo of recurring characters in the animated television series The Simpsons. Kang is voiced by Harry Shearer and Kodos by Dan Castellaneta. They are aliens from the fictional planet Rigel IV and appear almost exclusively in the "Treehouse of Horror" episodes. The duo has appeared in at least one segment of all twenty-three Treehouse of Horror episodes. Sometimes their appearance is the focus of a plot, other times a brief cameo. Kang and Kodos are often bent on the conquest of Earth and are usually seen working on sinister plans to invade and subjugate humanity.
The duo first appeared in season two's "Treehouse of Horror".
Virtually identical in appearance, one of the few distinguishing characteristics concerns the duo's voices as Kang's is deeper. In most appearances, they are antagonists. One exception is Kang and Kodos's first appearance in "Treehouse of Horror", where they capture the Simpson family and feed them exquisite cuisine. Lisa becomes suspicious of their intentions and accuses Kang and Kodos of wanting to eat the Simpson family. Kang and Kodos deny this accusation and are outraged. Afterwards both take the Simpsons back to Earth. Kang and Kodos have invaded the Earth on several occasions, with varying results. In 1996, Kang and Kodos impersonated Bill Clinton and Bob Dole and ran against each other in the 1996 election. At first, the Americans declared to vote for a third party candidate, but Kang convinced them that the option would be a waste of a vote. As a result, Kang was elected president. In their second appearance, they decided to take over the Earth after citizens had declared world peace, but ultimately failed.
Kang and Kodos have appeared in every "Treehouse of Horror" episode to date and have played major roles in "Treehouse of Horror I", "Treehouse of Horror II", "Treehouse of Horror VII", "Treehouse of Horror IX", "Treehouse of Horror XVII" and "Treehouse of Horror XVIII". The rest of their appearances were cameos, although both appeared in the opening segment of "Treehouse of Horror X", "Treehouse of Horror XIV", "Treehouse of Horror XV" and "Treehouse of Horror XVI". Kang and Kodos's cameo appearances normally occur in the midst of the segments which will suddenly cut away to the duo. For example, Kang and Kodos observe zombies attacking Earth from space. The duo laugh maniacally at the Earthlings's suffering, before the scene is switched from space to Earth. Kang and Kodos have made rare appearances in non-"Treehouse of Horror" episodes, such as "Behind the Laughter" and "Gump Roast", and had a non-speaking cameo in "The Springfield Files" on a line-up with other aliens. Also, the duo can be seen in "stop motion" in some of the newer Simpsons episodes, when it flies past the crowd of people.
An unofficial rule for the writers is that Kang and Kodos must appear in every Halloween episode. Despite this rule, the writers say the duo will often be forgotten and are added at the last second, leading to brief appearances.
Traditionally, Kang and Kodos appeared in every single Treehouse of Horror episode as a part of a story's plotline or as cameos. They almost did not make the cut in "Treehouse of Horror VIII", but David X. Cohen managed to persuade the producers to keep the scene. Kang and Kodos were originally going to make regular appearances in the show. One idea was only Homer would be able to see them and everyone else thinking Homer is crazy when he talked about the aliens. However the concept was "too far out", leading to characters only featured in the "Treehouse of Horror" specials. In some appearances, Kang and Kodos will laugh hysterically for several seconds. During production, the episodes would often be too short; so to make more time, their laughter was lengthened.