Ethan Thomas is the main protagonist and the playable character of the Condemned series. He's a Serial Crime Unit (SCU) investigator with Metro City.
At the start of the series he is working on 9 open Serial Killer cases. It just so happens once you take control, the investigation goes horribly wrong when he is ambushed at a crime scene by an unknown man and his gun is then used to kill two police officers. Ethan spends the rest of Condemned: Criminal Origins searching for the one who assaulted him while trying to stay steps ahead of the police, and solving some homicides on the way, all with the help of his Forensics specialist, Rosa (The only one who still trusts him). In the meantime he witnesses the depravity and insanity that has taken over the homeless and junkie population of Metro City. He also finds strange artifacts throughout the game which are artifacts of an ancient cult. Eventually he finds evidence of a tenth Serial Killer which he labels Serial Killer X. While tracking down SKX he finally finds the killer's home which leads to a showdown with him. As a result of this showdown Ethan loses a finger before he manages to escape from the killer. Ethan is told, by Malcolm Vanhorn (SKX's uncle, and your "family friend") that SKX was not always so bad, and that something is influencing. The game closes with Ethan hunting down the cause of the insanity and destroying it. Ethan is cleared of the murder of the two police officers in the end, but his experiences leave him mentally scarred.
As Condemned 2: Bloodshot opens, it reveals that in the 11 months since the events of the first game, Ethan has left the SCU and become a hopeless drunk who spends his time being angry at the world. SCU brings him back in to help with a case, and in the process more details are revealed about himself and the cause of the insanity that is gripping the town.
It is revealed that Ethan Thomas was in fact an orphan child. His parents were part of a cult called Oro Victus, a group that have access to supernatural abilities via special sound capabilities. His parents were eventually killed by Oro when they tried to leave the group, and Vanhorn immediately brought him in an orphanage to keep him secure from the members of Oro who were after Ethan because of his supernatural abilities. He was then raised without knowing of the Oro or his parents until the events of Condemned 2: Bloodshot. By the end of the game Ethan learns how to harness his ability to unleash bone-shattering sonic waves.
Ethan Thomas was voiced by Greg Grunburg. Grunburg is probably most famous for his role as Detective Matt Parkman on the TV show 'Heroes'. Interestingly, Thomas and Parkman share many similarities, both being detectives with supernatural powers that are psychic in nature.
In the second game, however, Thomas is voiced by Italian-American actor Andre Sogliuzzo. According to Monolith Productions, Grunburg was interested in reprising the role of Ethan Thomas for the sequel. The darker turn in story and character development (especially in Thomas' case) meant that in the end Monolith decided to find an actor who suited the role better.