Samuel "Sam" Axe is the best friend of Michael Westen, with a long career working in the military and who has had occupations from Navy SEAL to Military Intelligence operative. His long range of careers and operations has ensured a long list of "connections". However, with his espionage days behind him, he has started to become a moocher and drinks heavily. He is currently working with Michael and Fiona Glenanne doing various odd jobs. Sam Axe is portrayed by Bruce Campbell.
Once one of the world's top intelligence operatives, Sam has now become a laid-back slacker more concerned about where his next mojito will come from, and which one of his sugar mommas will let him use the apartment for the night. Even though he appears to be nothing more than a wash out, he still has his expertise intact and is very loyal to his friends. Sam has started to help Michael out on his various odd jobs, acts as his father figure and even occasionally lives in Michael's apartment whenever Sam is usually kicked out of a home by a current girlfriend. However, the FBI has tied up Sam's pension to force him to inform on Michael. Sam's loyalties remain true though, and he only reveals just enough information to keep them happy. He often uses the name Chuck Finley or some variation of it as a cover ID.
Sam apparently crossed paths with Fiona Glenanne, and Fiona had not forgiven him for getting her arrested for what she considered a "legal transaction". It appears that they have since put their disagreements aside to work with Michael.
Sam also serves as Michael's moral compass.
Occasionally, Michael will ask Sam to stay with his mother, Madeline Westen, so he can keep watch over her during dangerous jobs that could hit close to home. Sam has had to protect her from dangerous operatives in the course of duty such as Evelyn and Carla Baxter.
He is often seen wearing Hawaiian shirts, linen pants, loafers and flashy jewelry, including a pinky ring and Rolex watch, and is also sometimes seen wearing sunglasses.
Sam has many skills that are useful to Michael, including martial arts, wiretapping, burglary, marksmanship, forgery, interrogation, surveillance, and the ability to plausibly assume cover identities. His main contribution to the team, however, is his apparently inexhaustible supply of contacts (whom he calls "buddies") in seemingly every law enforcement agency, bureaucratic department, military branch and intelligence agency from the Florida DMV to the NSA, who are willing to share information.
- Throughout the seasons he is usually making some sort of drink and is regularly seen drinking beer, mojitos, or other alcoholic beverages.
- He appears to favor the Beretta 92FS as a sidearm, but has also various rifles to snipe and distract hostiles on jobs.
- Sam appears to be a left-handed shooter as he's almost always seen firing with a left hand when holding his sidearm; but he's also occasionally seen firing a rifle from a right-handed position. Ambidextrious shooting is a primary skill in marksmanship so it's not too absurd a thought that he'd be a proficient shooter with both hands.
- He seems to despise Larry Sizemore who upon meeting in "Double Booked", he asks, "Still drinking the blood of children?" and in "Out of the Fire", tries to bludgeon Larry with a piece of Rebar, only for Michael to restrain him and Sam leaves the flat in frustration although it has to be said to help Michael to turn the tables on Larry and Tyler Brennan. Sam later gets his revenge, though by freezing Larry with a sniper scope, buying enough time for Michael to escape and results in Larry finally being arrested by the police.
- His Favorite Cover ID is Charles Finley. He uses it a lot throughout the series and he says that "Chuck Finley is forever" in response to another character suggesting a different name due to the episode's target being named Charles (Chuck being a short, informal version of the name Charles). In "Down & Out", Sam claims it is his lucky identity.
- He got the name Chuck Finley in the TV movie Burn Notice: The Fall of Sam Axe.
- Sam went to Analy High School in Sebastopol, California and played football. This is the same high school the show's creator, Matt Nix went to.