Under the Dome Wiki

View of the Dome over Chester's Mill

The Dome is a massive, invisible field that encapsulates Chester's Mill. The National Guard has established a no-fly zone and at 10 miles out a guarded perimeter is in place around the Dome. Some residents of the town have speculated that it is sentient.[1][2]

Characteristics of the Dome[]

The Dome is an invisible field that surrounds the town called Chester's Mill. It appeared without warning, causing massive damage to whatever occupied the space it would take, including severing the arm of a woman who had been reaching across the arrival area, the legs of an person picnicking, cutting livestock in half and cleaving apart at least one home. The Doom’s sudden penetration of the ground extending deep below Chester's Mill initiated a brief earthquake.

The Dome severely interferes with radio communication and cuts off passage between Chester's Mill and the outside world; this means that Chester's Mill is cut off from outside electrical power, radio wave communication is so scrambled as to be effectively lost as are telephone, television, and internet cables, and goods that would normally enter it from the outside world are unavailable resulting in a resource crisis and shortages within.

Radio transmissions have been descrambled and received, however, though the work of Dorothy Weaver. This capability was lost when Dorothy was murdered by Big Jim, who covered up the crime by destroying the transmission tower and its equipment in a fire.

Electrical objects in the immediate vicinity (typically within several inches) of the Dome behave erratically and if not moved can be damaged and in the case of battery operated devices, explode. This resulted in Duke Perkins' pacemaker exploding in his chest,[3] Junior Rennie's flashlight exploding,[4] and Lester Coggins' hearing aid malfunctioning and causing a fatal wound in his head.[5]

The Dome has been stated to be roughly 20,000 feet in height which would lead us to believe that it would be about 40,000 feet in diameter.[6] At the geographic center at ground level a mini-Dome appeared, presumably at the same time as the larger dome. It was later revealed that the mini-Dome and the egg it contained were above a buried meteorite originally containing the egg that had impacted the spot 25 years earlier in 1988.

It is proven to be semipermeable, as some water was able to pass through it when touched by Joe McAlister.[7] The Dome appears to be almost completely soundproof, though a large explosion from a MOAB on the outside did register a sound audible inside. Though not particularly loud, the sound was nevertheless audible throughout the Dome.[5]

The Dome usually appears completely invisible in daylight, though it may have some slight refractive and reflective properties when viewed at a distance or at night. The Dome feel smooth to the touch, like a glass or plastic surface, once described as "smooth as a baby's bottom". Despite not being made of conventional matter, the Dome is either rough enough on a microscopic level or though simulated van der Waals forces allows matter to cling to it as they would to a normal solid. Only materials leaving a visible mark such as blood, paint, dirt and ash indicate its presence and give the illusion of floating suspended. Initial physical contact with the Dome can result in a slightly painful shock and accompanying low frequency hum with a whitish glow, but the effect diminishes upon subsequent contact and objects in continuous contact with the Dome produce no visible or auditory effects.[3]

The Dome is, for all practical purposes, completely indestructible. Vehicles crashing into the Dome (A box truck and small aircraft) were instantly destroyed, bullets bounce off, and most dramatically, a MOAB with an explosive yield of 11 tons of TNT equivalent produced no effect other than a slight noise.[5] Later on the Dome appears to protect Chester's Mill from a swarm of meteoroids and asteroids bombarding the Earth with the largest impactors possessing yields far in excess of the MOAB's. Though later shown to be an illusion, the event suggests that the Dome's invulnerability is far in excess of withstanding anything to strike it thus far, if not without limit.

The extent of how deep underground it runs is unknown, but it was discovered by Junior Rennie and Julia Shumway to extend deep into the underground tunnels of the cement factory.[4] By the Season 2 it's revealed that the Dome is actually a sphere explaining why no matter how deep people tryed to dig they would still hit Domes wall.

In the middle of the Dome there is another, much smaller dome that houses a small black egg. Joe McAlister speculates that it could be the energy source of the dome. Also it could be the reason why the Dome appeared in Chester's Mill.

The Dome can create apparitions indistinguishable from reality. In the episode Imperfect Circles the Dome using an apparition of Harriet's husband Greg makes her to touch the Dome for unknown reasons. In the same episode the smaller Dome that house the egg creates an apparition of Norrie's mother Alice and this way somewhat warns her that her mother is dying and she needs to see her. In Speak of the Devil the Dome creates an apparition of "Big Jim" and suggests that it wants that "Big Jim" would be killed. In Breaking Point it's shown that the Dome can create massive projections on its walls of alternate reality. It is shown creating a false projection of a swarm of meteoroids and asteroids (presumably of extrasolar origin) devastating the Earth and images of people attempting to flee being consumed by the resulting firestorm.

For unknown reasons the Dome made a connection with Joe McAlister and Norrie Calvert-Hill. They started to experience seizures and by both touching the Dome can somehow affect it. This is shown when after both Joe and Norrie touch the Dome the radio signal comes back in The Endless Thirst. They also able to communicate with it. Later on both James "Junior" Rennie and Angie McAlister joins Joe and Norrie as people who were somehow connected to the Dome.

In Season 1 final Curtains Alice apparition tells that the Dome exist so as to protect Chester's Mill from yet unknown disaster.

In Season 2 premiere episode Heads Will Roll the Dome shows the ability to magnetize itself. Created magnetic field is powerful to an extent that it will attract as heavy objects as cars or Chester's Mill church bell. Magnetic pulses also cause people to faint and if not threaten it can cause death.

The Dome can manipulate weather inside of it at will. This is shown on few occasions: first time is in The Endless Thirst when the Dome creates rain to stop the riot, second time is on Speak of the Devil where the Dome creates giant storm because of Junior deciding to leave the Egg. Also strange weather phenomenon can occur under it:on Season 2 episode Force Majeure acid rain starts to rain down on Chester's Mill and In the Dark dust storm begins to rage after the effects of acid rain in Force Majeure.

In Season 2 episode In the Dark it's revealed that there is a mysterious tunnel below the Dome. The tunnel possesses strange characteristics such as having two separate paths that are somehow connected as Sam and Barbie both went to two different directions but Sam ended up behind Barbie and a giant abyss that is at the end the tunnel. Another strange thing is the fact that the Dome's wall is non-existent in the tunnel even though earlier attempts to go below the Dome using cement factory's tunnels proved to be futile as all of them were blocked by the Dome. In episode Going Home it's revealed that the chasm in the tunnel is actually a portal to Zenith. It's also revealed by Joe McAlister that the tunnel didn't existed before the Dome came down. This leads them to think that the tunnel came with the Dome.

In Season 2 episode Black Ice the Dome shows the ability to change the climate under it by revolving and moving the cold air from high up to down below. Also in the same episode it is shown that the Dome has the ability to shrink it's size.

In Season 3 episode Alaska Christine Price reveals that without its power source, which is the egg, the Dome would eventually start to calcify and everyone under it would suffocate.

In episode Caged it's revealed that the Dome came down on Chester's Mill town because of Christine Price's interaction with the egg.


There has been speculation that the Dome does certain things deliberately.

Joe McAlister speculated that the seizures experienced by he and Eleanor Calvert-Hill were something the Dome "wants" to be kept secret, after unintentionally communicating so to the camera during an attempt to record their seizures.[1]

Julia Shumway later expressed her belief that the Dome was attempting to protect or placate the town, by protecting it from the military's missile, and later providing rain during the mass panic that water was in short supply.[2]

In Imperfect Circles the dome creates apparition of Alice Calvert somewhat warning that Norrie needs to go find her mom. As it turns out she dies and without the intervention of the dome Norrie wouldn't have talked for the last time with her mom.

In Speak of the Devil after Junior declaring that he doesn't want to be part of mini-dome secret, the Dome becomes somewhat angry and creates a giant storm. After Junior changes his mind the Dome makes the storm to disappear.

In the Season 2 premiere episode, Heads Will Roll, the Dome becomes enraged over Big Jim's actions to become the ruler of Chester's Mill by killing anyone who doesn't obey him and framing Barbie for those murders. It punishes Jim by nearly destroying Chester's Mill and his residence, only to be stopped by Julia who saves Big Jim's life and preserves it. The Dome then stops the destruction and becomes invisible again.

In episode The Fall the Dome creates an apparition of Angie McAlister so as to stop Junior from killing Sam.

In Move On and But I'm Not, the dome trapped everyone in these purple pods hooked up to an organic machine of sorts. It has put the residents in a dream like state where they think they have escaped the dome. Melanie is doing the dome's bidding, which still isn't entirely clear. Big Jim and Julia rescue everyone, causing Melanie to disappear and the organic machine to shut down.

In Caged, it's revealed that the Dome came down as a reaction to Christine Price's interaction with the Egg.


  • In the novel the Dome was up for only a week while in the TV series the Dome has been active for over four weeks.
    • Also the series version of Dome is actually revealed to be a sphere but because people can only see the top part of it they thought that it was a dome.
  • The dome acts more like a sentient being in the series, and can even create apparitions of people, show people "things", and may even be able resurrect the dead like Alice.. one of Norrie's mothers.