Disillusioned by his years as a spy, Robert McCall resigns from his job, determined to help people in need. His first two clients are a telecommunications employee who stumbles onto an extortion ring, and a woman threatened by a stalker.
A Chinatown gang kidnap whom they believe is the son of a wealthy Chinese-American couple, unaware that he is actually the maid's child. Fearful that the police will not be able to get the boy back alive, the maid contacts Robert McCall.
The Griffith family arrives in NYC on vacation from Duluth and things go wrong right from the start...their luggage is stolen by a gypsy cabbie and the hotel has lost their reservations. Bored and frustrated, Edie, the Griffiths 17 year old daughter wanders out of the hotel at night to do some exploring. She is lured into accepting a ride and finds herself abducted. The police can offer little help and with no one else to turn to they hire McCall to help find their daughter. His search will lead him into the seedy underworld of prostitution and an 'invitation only' ...
McCall meets an old Agency colleague who now hires himself out as a killer. His next target is an ambassador and his wife. He asks for McCall's help to save the wife because she is a woman they both used to love.
A bored housewife is dared by her friend to pick up a guy which she does. He takes her to a hotel room but when they arrive there's a guy already there. The guy who brought her there pulls out a gun and kills the man there. She runs away and calls McCall but she doesn't want her husband to know what happened. When she tells him what happened, McCall deduces that the man is a professional killer so they go to the police and she tells her husband. But the assassin tracks her down through her friend.
A doctor takes over an inner city clinic, upon arriving she discovers that the previous doctor has a deal with the gang who runs the neighborhood to provide them with drugs in exchange for letting them stay there. But when she learns of this, she tells them that it ends. The gang then threatens her but she's not intimidated. But her assistant knowing she's in over her head calls McCall. But upon meeting him, she refuses to accept help from because she doesn't believe in violence.
McCall is called by the tenants of an apartment building who are terrorized so that they would move out. They believe that the owner a wealthy man is doing this so he can tear down the building. McCall does a check on the man and discovers that he is looking for a hit man to kill his wife. So McCall approaches her and convinces her to come with him.
McCall assembles a team of former colleagues to help an innocent bystander in danger when he is unwittingly involved in a smuggling operation. However, McCall runs into unexpected trouble with a smug bureaucrat gunning for Control's job.
Two window-washers who want to form a union ask for McCall's help when they are threatened by their murderous employer. Meanwhile, McCall's housekeeper moves into his townhouse temporarily for a few days with her two young sons in tow.
McCall finds his attention divided when Jason Mazer from The Agency offers him a chance at revenge against an old enemy, while at the same time a young girl asks McCall to protect her and her mother against her abusive father.
A serial killer is targeting New York's lonely single women who respond to a Lonely Hearts newspaper ad. His calling card is an orchid he pins to the body. Meanwhile, McCall is writing an article about Robert E Lee for a military magazine and trying to help a young actress from being exploited by a pimp.
A womanizer is grabbed by some people who demand that he give them something that one of the women he's been with gave him. He has no idea what they're talking about so he turns to McCall for help. After going through all the women he knows they hit a wall. That is until he remembers one other woman whom he met briefly.
A man goes to the CEO of a corporation and accuses them of stealing his invention, and when he presents proof the CEO tries to destroy it. He then orders that the man be taken care of. And when they fail, the man's son calls McCall. McCall checks the CEO out and learns that he may have ties to a terrorist group, so he approaches the man in charge of the group and together they run a game on the CEO.