The Sierra program was a clandestine program overseen by the CIA that trained ‘Sierra Six’ among many others in ‘The Gray Man’.
The Sierra program had noble goals yet had questionable ways of getting there and when a new regime took over at the CIA, all traces of the old one began to be wiped out.
Donald Fitzroy visits Courtland Gentry in prison and after reading out his prison sentence, offers to commute it in exchange for service to the CIA for the rest of his life. He tells Gentry that he’ll be trained to kill bad people as part of an elite unit under the Sierra Program.
Fitzroy states that Gentry is the type of person who’s up for killing bad people as killing a bad person is why he’s in jail in the first place. He suggests taking all the pain and suffering he’s faced and turning it towards doing something useful. Gentry agrees and gets the designation ‘Sierra Six’.
Trouble in Thailand
Six is recruited for a job in Thailand where he’s supposed to take out a man designated ‘Dining Car’ who is looking to sell information that would threaten national security.
Six is accompanied by agent Dani Miranda who had planned the entire mission. Everything proceeds as normal until a child steps in the way of Six’s shot and he’s given the go-ahead for collateral damage.
The mission turns to chaos as Six chases after Dining Car and when he finally corners him, the target claims to be part of the Sierra Program, calling himself Four.
Four tells him that Denny Carmichael, the current DO at the CIA, is not to be trusted. He asks him to hold onto the evidence that he was selling and tells Six to “give ’em hell”.
The last of a dying breed
When his agents don’t find the evidence on Four’s person, Denny contacts Six and asks him if he took it but Six feigns ignorance before cutting off contact. Six then contacts a now retired Fitzroy to help him escape to someplace safe.
While questioning Dani about her possible role in Six’s escape, he tells her all about the Sierra Program and adds that Six is the last of a dozen agents, with the rest of them either dying or landing back in prison.
He talks about how Fitzroy chose to recruit hardened criminals and train them to be assets for the CIA in exchange for a commuted prison sentence. They were chosen for their skill set, lack of family and plausible deniability.
Their identities were destroyed and no record of their existence was ever maintained, essentially making them ‘ghosts’. They were expected to serve the CIA for the rest of their lives once recruited.
Denny is hellbent on getting rid of Six and retrieving the evidence he was given by Four which is why he enlists the help of sociopathic former CIA agent, Lloyd Hansen.