[2] Although he had a promising future in the military, he received a better offer from the federal government: a leadership position within the Secret Service, and was soon assigned to Caroline Reynolds (Patricia Wettig), whom he has served for fifteen years.

He eventually hardened into a ruthless fanatic, capable of suppressing his humanity to commit horrible crimes in the name of Caroline Reynolds.

Due to his commitment to her plans, he became a key figure in the conspiracy that framed Lincoln Burrows (Dominic Purcell) for murder.

Officially, as revealed in episode "The Rat", he is no longer listed as a member of the Secret Service or even as an employee of the Federal Government, and lives under the alias Owen Kravecki.

[3] Along with his partner and long-time friend Danny Hale, Kellerman's role in the first half of the season is to prevent anyone from uncovering the Lincoln Burrows conspiracy.

But when Caroline Reynolds is revealed to be dealing with sinister corporate powers- simply called "The Company"- Kellerman is shown making his opposition known to her about this.

Kellerman is eventually forced to kill his partner Hale, who has a crisis of conscience and attempts to betray the conspiracy in the episode "End of the Tunnel".

He is visibly upset that Hale planned to name him as a co-conspirator, giving Kellerman incentive enough to murder his old friend and partner.

Instead of directly involving himself in the manhunt for the "Fox River Eight", Kellerman decides to track Sara Tancredi (Sarah Wayne Callies), who he thinks will lead him to Michael Scofield (Wentworth Miller) and Lincoln Burrows.

Kellerman continues to follow Kim's orders, and puts pressure on the leader of the FBI manhunt, Special Agent Alexander Mahone, who is under blackmail from The Company, to secretly ensure the deaths of all the fugitives.

After he helps to obtain an audio file that could exonerate Lincoln in the episode "Bad Blood", Kellerman is abandoned by Sara and the brothers and instead decides to seek revenge on his own terms.

His character comes full circle when his suicide attempt fails and he calls his long estranged sister Kristine in the episode "Fin Del Camino".

Realizing that he did terrible things for nothing and that he has dedicated his life to a lie, a genuinely remorseful Kellerman breaks down in tears while his sister comforts him.

Now fully changed, the character plays a critical role in the episode, providing crucial help to bring down The Company.

Kellerman is shown talking on the phone to his ex-wife, discussing custody of his daughter, when Bagwell breaks into his home and holds him at gunpoint.

He starts to object to the taking of innocent people's lives, and shows genuine remorse when he is ordered to kill Sara Tancredi.

In the fourth season, he returns as a Congressman of great influence, well loved by the press and seemingly fighting corruption in the government, almost being completely the opposite of where he started out in the series.

"[5] According to issue #4 of the Official Prison Break Magazine, writer and co-producer Karyn Usher discussed Paul Kellerman.

An easter egg on the Season Two DVD release, in part a slideshow of all the characters that had been killed on the show, did not include Kellerman.