- "The time of vigilantes is coming to an end. Because how can you idolize someone hiding in the shadows who won't show his face? Who refuses to own up to his shortcomings and culpability? It's not a hero, it's a coward."
- —Samanda Watson to Oliver Queen[src]
Samanda Watson is a special agent of the F.B.I., she investigated Oliver Queen, the mayor of Star City; regarding if he is the vigilante known as Green Arrow. When Oliver desperately needed help to take down Ricardo Diaz, she offered the FBI's support in exchange for Oliver confessing his secret and being sent to Slabside Maximum Security Prison.
Investigating Oliver Queen
After a photo of Oliver Queen was circulated by Channel-52 News depicting him dressed up as the Green Arrow, Watson arrives in Star City to investigate him for his alleged crimes. During the investigation, she interrogates the other members of Team Arrow, except for Curtis, whom she hadn't been able to reach. It is later revealed that she confronted Rene Ramirez, having discovered his identity as Wild Dog, and blackmailed him into agreeing to testify that Oliver is the Green Arrow. If he refused to testify then she threatened to bring him down and would prevent him from being reunited with his daughter.
During Thanksgiving, Watson arrests Oliver for the crimes that the Green Arrow had committed. Oliver was taken into custody in front of his son, William, and Oliver promised that once he was released he would sue her for malicious prosecution. Watson did not care because she believed that she had all the evidence she needed to lock him up for good. She tried to convince him to sign a confession, but he refused and demanded to see his son. She later attended Oliver's trial, which was postponed temporally. After Oliver announced that the Anti-Vigilante Bill had passed, Watson confronted him and told him that she was returning to Washington, but she would be back for Oliver's trial.
When Oliver's trial was moved up a week earlier, Watson was not present in court for unknown reasons. Ultimately, Oliver was acquitted of the allegations against him.
Aiding Team Arrow
Sometime later, after Oliver was running out of options on how to deal with Ricardo Diaz's hostile take-over of Star City, he was left no choice but to go to her. Watson agreed to help him take down Diaz, but it comes with a price, half of it being admitting he was the Green Arrow, which he did with very little hesitation.
After they agreed on a deal, Watson sent in a number of F.B.I. agents into Star City to assist Team Arrow. They first raided the main police precinct and took out and detained Diaz's men. After a few skirmishes, one that nearly killed Watson and Rene Ramirez in a bomb, Diaz contacted them and demanded Mayor Quentin Lance to order the F.B.I. out of town, or else he would kill Laurel. After Quentin seemingly betrayed Watson just so that he could be close to Laurel, Oliver told her that Lance had a pacemaker which could be tracked before he left. Felicity hacked into the frequency of the pacemaker and tracked him down to Diaz's safe house. After a fight ensued between the combine forces of Team Arrow and the F.B.I. against Diaz's men, they rescued Quentin and Laurel. They also retrieved intel from Diaz's personal thumb-drive which were detailed files on his entire operation, which included those on his payroll, enough intel to liberate the city from Diaz's grip.
After the mission and Quentin was in the hospital undergoing surgery from a gunshot wound he received from taking a shot for his daughter, Watson came to arrest Oliver for breaking the law and would be sent to super-max prison. However, just before she took Oliver away, Oliver, the rest of his team, Laurel, and a just-arrived Sara Lance received word from Dr. Schwartz that Quentin Lance died. Watson told Oliver that sadly this changes nothing, despite her feeling sorry for his loss and escorted Oliver out. After a last visit from Felicity Smoak and Oliver's son, William, Oliver with Watson held a press conference and Oliver told the world he was The Green Arrow and was going to jail. He told the city that others will carry on the fight for him in his absence. While that was going on, Diaz went into hiding with his new allies while, under Samanda's orders, the F.B.I. arrested all those on Diaz's payroll, thus freeing the city from Diaz's hold over it.
After which Watson took Oliver in and brought him to prison, completing her duties.
Chasing Ricardo Diaz
Five months later, even though she is fully blamed for putting Oliver in prison and started the anti-vigilante law in the first place. after Felicity failed to capture Ricardo Diaz with A.R.G.U.S.'s help, she goes to Agent Watson and demand to fulfill her end of the deal she made with Oliver and help her take down Diaz, once and for all. Watson tells Felicity to go home, enjoy her freedom, and leave the crime fighting to her. Felicity then leaves not before giving Watson a piece of her mind and even tells her how the Longbow Hunters are in Star City. After Felicity is gone, Watson calls a meeting with her superior to inform her about the lead on Ricardo Diaz and of the Longbow Hunters now being in Star City. However, Watson's superior proves to be unreasonable since he believes Diaz to no longer be a threat after dismantling his hold over the city. Watson then tries to press further by informing her boss that Diaz hacked into the Center of Disease Control's computer network, however, Watson's boss tells her that going into the Center of Disease Control requires a level 5 clearance which she clearly does not have. When Watson protests, her boss tells her to inform the Center of Disease Control that they have been hacked and to focus on other cases while reminding Watson that she works for him.
Watson's superior then leaves and Watson tosses the Diaz file on her desk, clearly disappointed by all this. Watson later meets with Felicity, Dinah Drake, and Rene at the S.C.P.D. precinct where Felicity convinces everyone to go off-book to catch Diaz at the C.D.C. by setting a trap for them there. Watson reluctantly agrees to it and the four of them arrive there after Watson gives them F.B.I. jackets. Watson leads the team as they try to stop Diaz and the Longbow Hunters from stealing chemicals from the C.D.C. only to fail. Watson's boss then becomes enraged at this and assigns Watson to a desk job in Washington since Watson had no clearance to be at the C.D.C. While she is packing for her new life, Watson calls Felicity to her office showing compassion for her as well as acknowledging that disobeying her boss was the right thing to do. Watson then feels guilt that Diaz got away and wished that either Diaz or one of the Longbow Hunters were captured since things would have been different if that have happened. Unknown to Watson, Rene did capture the Silencer under instructions from Felicity. The reason Felicity did not want to tell her that is due to having lost faith in law enforcement.
- "Just because the system is flawed doesn't mean it shouldn't exist. Even someone like Ricardo Diaz needs a lawyer, a fair trial. We protect the rights of people who don't deserve them 'cause it's the only way to protect them for everyone."
- —Samanda Watson[src]
Watson is similar to Quentin Lance at first; as she is going after Oliver Queen, also known as Green Arrow, because he is a vigilante (disregarding the fact that vigilantes are not in the F.B.I.'s jurisdiction; it is in the jurisdiction of local law enforcement) she is very calm and level-headed, as she did not display any signs of anger when she was interviewing each member of Team Arrow respectively, to gather evidence that Oliver is a vigilante. She is ruthless as she arrested Oliver at a Thanksgiving event for the crimes charged on Green Arrow in front of his son, proving that she doesn't care how she prosecutes her suspects in front of the people close to them.
Watson is very arrogant to the point of having a massive ego, as she believes being an F.B.I. agent makes her superior to Oliver who is the mayor of Star City; legally it doesn't (proving just how deluded she is) when she was in the mayor's office waiting for Oliver (despite the fact that she didn't make an appointment to see him) she (arrogantly) told him she didn't give a damn, when Oliver could've had her arrested for illegally trespassing in the mayor's office (as she did not have a search warrant or a warrant to question him); her arrogance is also to the point of being delusional, as she believes because she is an F.B.I. agent, that the laws don't apply to her; legally it does.
Watson is quite immoral and dishonorable; when Oliver was away with Slade Wilson, she interrogated Oliver's teammates "thus widening her net" behind his back, a sign that she will use and go after anyone close to him to gather evidence and blackmail anyone to testify against Oliver.
Watson does seem to have a sense of humor, as she took time to taunt Oliver on how he couldn't stop Ricardo Diaz as Green Arrow or the mayor despite knowing fully well the answer and also lightly mocked Rene Ramirez for how bad he was at keeping his vigilantism career a secret.
Despite her negative behavior, Watson is revealed to have a tender side, as evidenced by the fact that before she arrested Oliver, Watson did express some sadness for the death of Quentin Lance, saying that this sadly changes nothing for their arrangement. She is completely unaware that the Star City crime wave and corruption started when she arrested Oliver and the anti-vigilante act started. Despite being loyal to her boss and to the F.B.I. as a federal agent and despite all her corrupt methods, Watson still has a sense of honor, as acknowledging that her deal with Oliver was not fulfilled as Diaz was still out, she was willing to go out of her way by disobeying her boss to help Felicity Smoak track down and capture Diaz, even going as far as putting her own life in danger against the Longbow Hunters. Watson also appears to have good morals and principles since she believes everyone, including people like Ricardo Diaz, have the right to a lawyer and to a fair trial.
Agent Watson also seems to have a soft spot for Felicity Smoak. After Diaz and his crew escaped, Watson later called Felicity for a meeting at her office, revealing that she has been demoted to a desk job by her unreasonable boss at Washington D.C. as punishment for disobeying him. Watson admits to Felicity that although she believes good law enforcement does make up for the bad, disobeying her boss as well as going off the books to catch Diaz was the right call to make. Watson then verbally acknowledges Felicity as a good person and that she doesn't deserve to be without her family, hinting that she truly is remorseful for having sent Oliver to the Slabside Maximum Security Prison.
- High-level intellect/Expert investigator/Leadership: As a high-ranking F.B.I. agent, Watson is a very intelligent woman and excellent investigator, able to follow every lead to discover the truth behind any crime. Watson was able to figure out that John Diggle is posing as Green Arrow, to divergent suspicion that Oliver Queen is a vigilante, who is under investigation by the F.B.I. (albeit without any evidence); she also somehow discovered that Oliver was previously the vigilante known as the "Hood/Arrow" and that John poses the vigilante archer clearing the latter suspicion of being a vigilante. She also has excellent leadership skills, having led a group of F.B.I. agents sent to help Team Arrow battle and defeat Ricardo Diaz despite his control of the Quadrant, a massive group of dangerous criminals.
- Expert hand-to-hand combatant/Martial artist: As an F.B.I. agent, Watson is highly trained in unarmed combat, allowing her to hold her own against Red, a member of the Longbow Hunters, and briefly stalemate her but struggled to do so.
- Expert markswoman: As an F.B.I. agent, Watson is well-trained and proficient in the use of firearms. She was able to shoot down many of Diaz's men.
- Samanda has similarities to the late Amanda Waller and Smith; all three are individuals in positions of high government who, despite their obligation to the law, arrogantly believe they are above the entity and thus not afraid to resort to dishonorable and immoral acts to achieve their goals, which puts them at odd with the heroes.
- Unlike Smith and Waller though, Samanda ultimately has an honorable side and is willing to work with the heroes to take down mutual foes.