Auldridge (introduced in "Born to Run"), portrayed by Joshua Malina, is an FBI Agent who handles difficult unsolved cases involving unusual evidence or facts.
Father Armando Bonilla (introduced in "Samson and Delilah"), portrayed by Carlos Sanz, is a priest to whose church Sarah and John Connor flee when escaping from a malfunctioning Cameron.
During a meeting with FBI Special Agent James Ellison in a deleted scene of the episode "The Turk", it is implied that Carlos also forged identification and allied documents for Derek Reese and his unit at some point after their arrival from 2027.
Vick Chamberlain, portrayed by Matt McColm (introduced in "Gnothi Seauton"), is a T-888 Terminator sent back in time to help create a traffic surveillance network that Skynet hopes to use in the future.
An advanced infiltrator, Vick poses as the husband of city manager Barbara Chamberlain, murders one of her political enemies, and adapts his mission to attack a group of Human Resistance fighters, including Derek Reese, when he finds one of them spying on her.
She attended culinary school with a classmate who knew George Laszlo, and met Nick's policeman father, Trevor (Jon Huertas), when she was a 25-year-old pastry chef in Silver Lake.
Operating Cromartie's former head as its avatar, the Babylon AI politely greets a shocked Ellison and identifies itself as "John Henry", a name recently given to it by the late Dr. Boyd Sherman.
The endoskeleton structure contains some upgrades, including additional armor plating to protect the spinal column and chest, as well as bladed surfaces on the inner thighs, allowing a (presumably fleshless) T-888 to kill a human if it can get them in a headlock between its legs.
Charley Dixon, portrayed by Dean Winters (introduced in the pilot episode), is Sarah Connor's fiancé in 1999 before she leaves him, fearing discovery of her true identity and thus her son John's death.
He was subsequently sent back in time by Skynet on a mission to create a backdoor in a vital defense database at the firm where he worked before prison (and thus had access through his retinal scan and fingerprint).
Jesse Flores (introduced in "The Tower Is Tall But the Fall Is Short"), portrayed by Stephanie Jacobsen, is an Australian Human Resistance sailor with the rank of commander and Derek Reese's love interest.
In the episode, "Strange Things Happen At The One-Two Point", Jesse confesses to Derek that she didn't merely return from the future AWOL, to escape circumstances she could no longer bear, but rather she is on a mission to find and stop Cameron from adversely influencing young John.
Andrew "Andy" David Goode (introduced in "The Turk"), portrayed by Brendan Hines, was a young college dropout from Caltech who interned with Cyberdyne Systems, and worked as an assistant to Miles Dyson.
Having failed in her studies at the California Institute of the Arts and being rejected by her parents, she becomes a prostitute and thief, living for a time in a halfway house on Yucca Street in the Hollywood district of Los Angeles.
The T-1001 posing as (the long deceased) Catherine Weaver then assumes Kaplan's appearance and re-interviews an eyewitness who admits to seeing Ellison emerge naked from a blue-purple energy bubble that left a "dent" in the street, and snap the victim's neck like a toothpick and steal his clothes.
Matt Murch (introduced in "Samson and Delilah"), portrayed by Shane Edelman, is the lead engineer and programmer in Project Babylon that evolved into the AI dubbed John Henry.
Perry dispatches Reese on a dangerous mission to Eagle Rock Bunker to rescue Sydney Fields and bring her back, so that their scientists can isolate and reproduce her immunity to Skynet's biological weapon.
In "Dungeons and Dragons", Perry sends Reese and his team back in time to 2007 to capture and destroy Andy Goode's Turk chess computer (which evolves into the AI dubbed John Henry) and otherwise prevent Skynet from being created.
In the episode "Goodbye To All That", during one of Derek's recollections of the future war, Kyle (when he was a Corporal) and a small group of his unit attempted to save forty prisoners, including General John Connor, from Skynet's forces.
Enrique Salceda (introduced in "Gnothi Seauton"), portrayed by Tony Amendola, was an expert at forging identities and helped provide the Connors firearms during Terminator 2: Judgment Day, but retired from the business and passed it on to his nephew, Carlos.
Margos Sarkissian (introduced in "What He Beheld"), portrayed by James Urbaniak, purchased Andy Goode's Turk chess computer (which will later evolve into the AI dubbed John Henry) and pursued the Connors, in order to blackmail them out of $2 million.
A man (seen in "What He Beheld"), portrayed by Craig Fairbrass, whom the Connors believe to be Margos Sarkissian, contacts Sarah and offers to sell her the Turk, but then later threatens to expose her to the FBI unless she pays him $2 million.
Sarah Connor brings her family to his care in order to figure out what his role in Skynet's future is, because his name is on the blood list left by a dying Human Resistance soldier on their basement wall.
In the television show, Peter Silberman first appears in "The Demon Hand", portrayed by Bruce Davison, and maintains the continuity from Terminator 2: Judgment Day, being the Chief Psychologist who treated Sarah Connor while she was institutionalized at Pescadero State Hospital.
Myron Stark (introduced in "Self Made Man"), portrayed by Todd Stashwick, is a T-888 who accidentally arrives in Los Angeles from the future on the night of December 31, 1920, due to a temporal error in the time displacement chamber.
T-888, a model of Terminator, examples seen in the characters Cromartie (who later takes the form of the deceased George Laszlo and eventually becomes the avatar for the John Henry AI), Vick Chamberlain, Myron Stark, and Queeg.
Mr. Walsh (introduced in "Samson and Delilah"), portrayed by Max Perlich, is a violent thief hired by the T-1001 posing as (the long deceased) Catherine Weaver to obtain Andy Goode's Turk chess computer for her, for a fee of three hundred thousand dollars.
Catherine Weaver (portrayed by Shirley Manson), her husband Lachlan (Derek Riddell), and their young daughter Savannah (Mackenzie Brooke Smith) are introduced in the second season.
In a scene from the extended DVD cut of the episode The Demon Hand,[12] John examines her school locker, finding graffiti similar to that which prompted student Jordan Cowan to commit suicide.
John Connor later meets Allison in an alternate timeline in the episode "Born to Run", where he never leads the Human Resistance due to his displacement from his present resulted by time travel.