In the pilot episode, what is originally thought to be a comet deposits a group of exactly four thousand, four hundred people in the Seattle, Washington region. All of the 4,400 had disappeared at various points starting from 1941 in a beam of white light. After their return, none have aged, all are disoriented, and they remember nothing between the time of their disappearance and their return.
NTAC (National Threat Assessment Command), a division of the Department of Homeland Security, is formed in response to the return of the 4400. There are a multitude of agents assigned to the case. The series mainly follows two of them, as well as their immediate superior:
Tom Baldwin: Baldwin's nephew is Shawn Farrell; Shawn was with Baldwin's son Kyle Baldwin during the abduction. Kyle was in a coma for three years, and after being awoken is troubled by blackouts.
Diana Skouris: Tom's partner. The eight-year old pre-cog Maia asks to move in with her at some point in season 1. In the first episode of season 2, Diana adopts Maia Rutledge.
Dennis Ryland: Baldwin's and Skouris's supervisor and director of the Seattle bureau of NTAC during season one.
Ryland is succeeded by Nina Jarvis in season two, but he takes his role back as a guest star on the 11th and 12th (season finale) episodes of season two.
Most have trouble trying to get their lives back on track after being separated from their world for years. More significantly, a small number of the returnees begin to manifest paranormal abilities, such as telekinesis, telepathy, precognition, and much stranger ones. In addition, one of the 4400 had become pregnant between her disappearance and return.
At the end of the first season, we learn that the 4400 were abducted, not by aliens, but by someone in Earth's future, and that they were returned in order to prevent some sort of catastrophe.
At the end of the second season, it was revealed that all 4400 had a new neurotransmitter called "promicin" in their brains; it was this which gave some of them their powers. The government, afraid of what this large group would do with such power, secretly dosed all 4400 with a promicin inhibitor. (It worked on the majority of the group, but not those who were later seen with powers.) The inhibitor caused a potentially fatal immune system condition in the returnees, forcing the government to inject all surviving returnees with replacement promicin; it is hinted that all of them will now exhibit powers.
The series follows the lives and stories of a select few of the 4400. The main characters are:
Richard Tyler, disappeared May 11, 1951, at age 29, while in South Korea during the Korean War. Originally from St. Louis, MO. At the time, in a relationship with Lily Moore's grandmother, Lily Bonham. Father of Lily Moore's second daughter, Isabelle. Paranormal abilities: apparent telekinesis
Lily Moore, disappeared in 1993, at age 26, from St. Louis, MO. At time of abduction, married to Brian Moore, mother to Heidi Moore. Returned pregnant, but not by Brian, rather by Richard Tyler. Paranormal abilities: None Known.
Shawn Farrell, disappeared April 22, 2001, at age 17, from Highland Beach, WA. Paranormal abilities: Healer and life taker.
Maia Rutledge, disappeared March 3, 1946, at age 8, from Crescent City, CA. Paranormal abilities: precognition.
Jordan Collier, disappeared April 10, 2002, from Seattle, WA area, a former real estate mogul. Paranormal abilities: unknown. Possibly enhanced power of suggestion over other people, but this could just be a personality trait. Also, after being assassinated, he disappears and reappears alive at the very end of the second season finale.
Isabelle Tyler-Moore, born post-return, daughter of Richard Tyler and Lily Moore. Technically not one of "The 4400" returned (she was still in the womb at the time of the count). As the only 4400 not affected by the ability-inhibitor, she provides blood used to heal Shawn Farrell and consequently all 4400s, activating their abilities. At the end of the season finale she ages considerably and shows up in Shawn's office, naked. Paranormal abilities: Telepathic communication (with Lily Moore, Richard Tyler, and Jordan Collier), mind control, materialization projection, healing (Jordan Collier's injury, Lily Moore's first daughter's spleen) and/or acceleration of biological growth (the growth of berries in one episode and herself in the Season 2 finale), precognition (warned Lily of a bomb before it exploded), telekinesis (the bending trees in the final scene of Season 1). Note that many of these powers duplicate those from among the 4400.
Several other members of the 4400 feature in specific storylines:
Carl Morrisey, disappeared February 16, 2003, from Seattle, WA. A supermarket employee (Deceased). Paranormal abilities: Enhanced reflexes and strength.
Oliver Knox, disappeared August 22, 1983, from Friday Harbor, WA, a suspected serial killer. Captured and imprisoned in soundproof cell. Paranormal abilities: Mind control/suggestion via speech.
Tess Doerner, disappeared April 3, 1955. A mental patient. Paranormal abilities: Ability to compel others to help her build a device, the plans for which have been planted in her head.
Gary Navarro,disappeared January 5, 1973. A baseball player. Paranormal abilities: Is able to hear the thoughts of others.
Trent Appelbaum, disappeared May 18, 1989. A telemarketer. Paranormal abilities: Saliva contains an agent that rapidly accelerates the metabolism of others.
Orson Bailey, disappeared June 11, 1979, from Tacoma, WA. Insurance Salesman and partner in Kensington & Bailey. Paranormal abilities: Telekinesis of a magnitude to cause tremors in immediate vicinity and shatter objects (e.g. glass, bones). The ability does cause Orson to suffer nosebleeds, and he has shown an inability to control this power. He was shot during apprehension, but lived.
Alana Mareva, disappeared September 5, 2001. Artist (and debatably museum director). Paranormal abilities: Ability to create an alternate reality. Given to her by the future so she can develop a relationship with Tom Baldwin to sustain him through the "coming troubles."
Mary Deneville, disappeared August 4, 1999. (Deceased) Paranormal abilities: Could revive dead plants.
Eric Papequash, disappeared August 5, 1955.
Heather Tobey, school teacher, disappeared March 2, 1974. Paranormal abilities: Unlocked artistic potential in certain students in her classes.
Jean DeLynn Baker, disappeared October 27, 1999. (Deceased) Paranormal abilities: sores on hands released plague-like disease (airborne, disappears in about half an hour, goes through biohazard gear).
Edwin Mayuya, aka Edwin Musinga, doctor, disappeared February 24, 1996. Paranormal abilities: Could heal fetuses in utero (but causes progressive damage to self).
Roger Wolcott, disappeared March 6, 1987. (Deceased)
Sara James, disappeared November 5, 1971.
Laurel Bryce, disappeared January 7, 1982.
T.J. Kim, disappeared February 2, 1998. Paranormal abilities: Increases the levels of adrenaline or other hormones (causing elevated levels of rage) in males within a certain radius through sonic means.
The abilities of the 4400 derive from activating dormant neural pathways. Apparently the body produces four main neurotransmitters that control and regulate everything. Every 4400 produces a fifth neurotransmitter called Promicin that enables him or her to use parts of the cerebellum no human has ever had access to. Promicin's behavior and effect are unpredictable, potentially giving any ability.
This plot element uses the "Ten Percent Myth", which modern science has disproven.
The promicin-inhibitor would piggyback on glucose. It entered the brain through facilitated diffusion. It's a binding protein. A serum was created that contained pure promicin. This serum neutralized the charge so the inhibitor isn't able to cross membranes and can be flushed out of the body.
Filming has begun on the upcoming third season of sci-fi drama The 4400 ahead of its summer premiere on the USA Network and Sky One.
Billy Campbell is reprising his role as Collier, the self-anointed leader of the 4400, for the new season, while Peter Coyote returns as Dennis Ryland for the two-hour premiere.
New cast members include Tippi Hedren "in a role that is sure to surprise fans of the series" and Karina Lombard joins as a series regular playing Alana Mareva. Megalyn Echikunwoke is also joining the cast as "the newly grown-up Isabelle".
The first four episodes of the third season are "The New World", "Being Tom Baldwin", and "Gone" parts one and two.
In an interview co-creator Scott Peters states that in the first three episodes a romance may develop between Shawn Farrell and the grown-up Isabelle, along with revealing other possible plot developments.
In an interview with Joel Gretsch, who plays federal agent Tom Baldwin, the actor states that his character gets pushed to his limits in the two-part episode "Gone" which deals with what appears to be the disappearance of Maia.
The 4400 Center run by Jordan Collier seems intended to resemble the real-world Church of Scientology. The 4400 Center promises supernatural abilities to those who follow its training through for-pay courses, much as the Church of Scientology promises, though Scientology is not as forthcoming about its promises of supernatural powers. At least one 4400 Center attendee has had his psychological medication confiscated, much as the Church of Scientology is opposed to psychology and its medications. The 4400 Center includes technological devices strapped onto its members during courses, similar to Scientology's E-Meters. The 4400 Center targets celebrities for inclusion and promotes them through the program faster than non-celebrity members; the Church of Scientology definitely intentionally draws celebrities with its "Celebrity Centers". One former member of the 4400 Center accused it of making him take endless for-pay classes until he was bankrupted, at which point he was ejected from the program; Scientology has had similar accusations pointed at it.
The name of the show itself might be an allusion to the belief held by Jehovah's Witnesses that only 144,000 people will be allowed into sky. The 4400 people who disappear do so in a rapture like fashion. The show's content has subtle Christian undertones, although not in a way that one would take it to be proselytizing. The baby Isabelle, believed by some to be the future savior of mankind, has no qualms about violently killing people who get in her way. While Isabelle might sometimes seem like a Christ-like figure, she is certainly not. In the same vein, Jordan Collier (note his initials JC), whose intentions and methods are also grey, is killed by a sniper, and after his funeral, his body miraculously disappears. He is then reborn (albeit in a currently unknown fashion).
The Chan Centre for the Performing Arts, standing in as The 4400 Center during filming.
Even though the series is set in Seattle, it is filmed in Vancouver, British Columbia. All the cars have fake Washington license plates and The 4400 Center is actually the Chan Centre for the Performing Arts at the University of British Columbia. There is another nod to the filming location in the opening credits -- the vintage car in the opening video has "Beautiful British Columbia" license plates.
Sony's PSP, Budweiser and other products are placed prominently within in the series, often awkwardly clashing with the storyline. For example Jordan Collier attempts to give a PSP to the 8 year old girl Maia which does seem out of place for a product marketed to teenagers. Budweiser is featured in 330ml cans, and it is commented that this just how they drank it during the Korean war. These styles of cans were not brought out until long after the war's end.
In Australia and New Zealand the first series was shown as a miniseries of 2 episodes. The second season was aired weekly but taken off air halfway through the season, but continued to air in New Zealand. In February 2006, it was put back on air, starting from where it had left off.
Early marketing for the series included stencilled graffiti in public places across San Francisco, Houston, and Boston raising ire among residents.