|Occupation||Criminal and Forensic Science assistant for Central City Police Department|
|Family||Henry Allen (father)|
Nora Allen (mother; deceased)
When Barry was eleven years old, he saw a tornado-like blur sweep through his house, in the middle of which he could see a figure. His father went to fight it and soon after Barry went to help. Somehow instead, he was swept twenty blocks away from his house. He soon discovered that his mother had been murdered and that his father arrested for it and incarcerated with a life sentence, despite his witness accounts of the blur. Since he was so far from the crime scene, officials believed he was merely covering for his father. This motivated him to study criminology in the hopes of proving that his father is innocent. 
Visit to Starling CityEdit
Years later, Barry arrived in Starling City. He wasn't able to initially get a cab as the driver pulled away, and he soon arrived at Queen Consolidated's applied sciences division to investigate a mysterious break-in as a CSI from Central City with a connecting case, where he met Oliver Queen, John Diggle, Quentin Lance and Felicity Smoak (the latter whom he had an instant connection with).
He was set up in the division with Felicity's help, unknown to Barry, because Felicity believed that they should use him as an asset since forensic science is not the expertise of any of their team (namely Felicity, who does most of the information gathering and recon). The two began talking, and Barry began speculating about the Arrow and his background, making incisive observations about why the Arrow wears green instead of black, the type of arrows he has used, and how he theorizes the Arrow has partners, particularly someone who had a background in computer sciences, unnerving Felicity.
He was astounded when Felicity asked him to help with a blood sample from an arrow she received from the police both by her "connections" from working for Oliver and the fact that he was working the same case as the Arrow. During this particular part of their investigation, Felicity invited Barry to a Q.C. function/Queen party. However before the results came in, his cover as an crime scene investigator working for the police was blown by Oliver just after he and Felicity began arguing over a news report about the mass particle accelerator. It turns out he is just an assistant CSI and there was no connecting case in Central City. Barry explained what happened to him as a child caused him to begin looking into cases with impossible circumstances, in hopes of one day proving one possible. If he can do that, he may be able to solve his mother's murder and free his father. Later on, he was re-invited by Oliver as Felicity's plus one to come to his home where he was throwing a party for his mother where he apologized to Felicity while they danced.
After the party, Barry was contacted by his boss and was told to return to Central City if he hoped to keep his job, and revealed the sedative used as Ketamine, informing Felicity it should be easy to track. He tried to catch the next train back but he just missed the last one of the night. He settled the train station to wait for the next one in the morning when he was hit with a tranquilizer dart to the neck. When he awoke, he found himself in Oliver's base with Diggle watching him and Oliver lying on a table in full vigilante costume. Felicity approached him and asked Barry to save Oliver's life who was not only poisoned with an unknown substance from the A.R.G.U.S. disaster bunker, but also had been beaten by the robber who had stolen the centrifuge from Queen Consolidated, raided the blood bank, and encountered Oliver as the Arrow while stealing large amounts of Ketamine from the bunker.
Barry is described as someone who compliments Felicity Smoak's intellect level both when it comes to forensics as she claims its not her strong suit and science in general. He also someone who is almost always late as he missed a train, boarded a late train, and misses a cab all to get to Queen Consolidated's warehouse and missed the last train back to Central City. He is also considered a comic geek.
Much like Oliver, he has a strong sense of justice, due to the fact he knows his father is innocent of a crime he was convicted of and is still serving a life sentence. He joins the forensics department to both learn how to investigate crimes, and study cases with unexplained elements, to prove his personal account of his mother's murder true, and ultimately, free his father.
- He tends to be late for everything, a homage to the fact that in the comics Barry would be late for everything to keep his identity as The Flash a secret, though in the Arrow universe it's just because he's unlucky.
- He knows a lot about the previous actions of the vigilante and tells Felicity several ways in which the Arrow can improve his methods. He has many accurate theories about the Arrow - believing that he trained in a tropical environment because of his green clothing, and that he has one or more accomplices, including one with a background in computer sciences.
- Barry is the twelfth person to discover Oliver's secret identity, The Arrow. He discovered this in "The Scientist".
- The original comic-version of Barry Allen has blond hair where as the Barry Allen in the Arrow universe has dark brown hair.
- In "Three Ghosts", Barry Allen received his powers as a lightning bolt struck a shelf of chemicals in his lab and the combination of the two accidents led to his abilities. This is a nod to how he receives his powers in the comics.
Behind the scenesEdit
- In the DC multiverse Barry Allen is the second person to take up the superhero mantle of The Flash.
- In 2014, The Flash will be the third DC-owned character to have its own television broadcasted show on The CW, following Smallville and Arrow.