- For his Earth Two equivalent, see Barry Allen's father. For his Earth Three equivalent, see Jay Garrick.
- "Hey slugger."
- —Henry Allen to Barry Allen[src]
Dr. Henry Allen (1955-May 17, 2016) was the father of Barry Allen, the husband of the late Nora Allen, and a good friend of Joe West. Henry was framed by a time traveling known as Reverse-Flash who had killed Nora and sent to prison. Along with the people at S.T.A.R. Labs, and Joe and Iris West, he also knows Barry's secret; that his son is the Flash. After Eobard Thawne was erased from existence, Barry was given a recording where the former confessed to murdering Nora Allen. Henry was released from prison, though he told his son he had to leave town as he didn't want to get in the way of his son being a hero. However, after seeking advice from Henry months later, Barry returned to Central City with him where he made a final decision to stay. Soon after, Henry was murdered by Hunter Zolomon. However, after Hunter was defeated, Barry went back in time to prevent his mother's murder, resulting in Henry being alive in the new timeline. However, Barry soon realize that he made a big mistake of creating this timeline, and he allowed the Reverse-Flash to kill his mother a second time, so that the timeline would restore to the way it was, but different.
Originally, Henry never had been killed by Zoom and lived at least until 2024 when his son traveled back in time as The Flash to stop Reverse-Flash, which resulted in a new timeline.
In 2000 when his son, Barry, was 11 years old, a red and yellow tornado-like blur came into their home, and in the middle of the tornado seemed to be a man. Henry held Barry back, telling him to run, and before either of them could do a thing, the blur shoved and knocked Henry out, murdered Henry's wife and swept Barry 20 blocks away from his home. Following Nora's death, her murder was pinned on Henry and he was sent to jail in Iron Heights Prison.
Henry disallowed Barry from seeing him as he didn't wish him to see his father in jail. However, Barry eventually snuck in by running to the prison. Henry assured Barry that he couldn't help him in any way, so instead he wished him to be the good boy that both of his parents believed he was.
Incarceration in Iron Heights
15 years later, in late 2014, Henry was still incarcerated in Iron Heights. He had Barry come to visit him from time to time, and despite him previously having told to change his name out of embarrassment, Barry stated that he was incredibly glad that he didn't, as he was more than proud to be Henry's son.
Eventually, Joe went to visit Henry. Joe explained that Barry was fine, he had just felt like it was long since due that he visited Henry. He promised that he finally believed Henry, that he knew he hadn't killed Nora, and he was finally reopening the case. He apologized, though Henry stated that he never cared about Joe's belief in him, but his belief in Barry. Suddenly, The Mist entered the room and began suffocating the guard. He soon moved on to Joe, causing him to choke, before Barry came, in disguise, and saved him with a counteracting injection. Henry watched as the seemingly unidentified man saved Joe's life. Barry turned towards his father, blurring his face so he wouldn't recognize him; Joe soon came back to life and Barry ran off to stop The Mist. Barry later came to visit his father. He expressed how he missed his mother, which led to Henry telling a story about when Barry learnt to walk: being a late bloomer, Nora believed that he'd walk when he had some place to go. Finally he learnt how to walk, but rather than walking, he ran in to his mother's arms, finally having some place to go.
When the man in yellow reappeared in Central City, Barry visited his father again, saying he had had his mother's murderer but let him escape, and saying that because he had failed to stop him, he was now partly responsible for Henry's imprisonment. Henry told Barry not to blame himself, that the man in yellow had already taken enough from their family, and that Barry should live his life rather than let Nora's killer take anything more from them. He also revealed that he had long known about Barry's unspoken love for Iris.
During Barry's investigation of Clay Parker's breakout of Iron Heights, Joe arranges for Henry to be moved by a police officer past the crime scene so that him and Barry could enjoy a short time together. Later, without Barry's acknowledgement, Henry asks around the inmates for information on Clay so as to assist the investigation. Barry tells Henry to not endanger himself anymore, which Henry consents to. Despite this, Henry stays in contact with Joe and continues to search for more information. As a result he is stabbed and beaten by Julius, an inmate working under Marcus. He reveals that he continued to investigate because he wanted to be there to help Barry like Barry did for him. At Barry's insist, he tells him Julius harmed him.
The next day Henry is seen in his infirmary bed, discussing Barry's recent date. He then mentions The Flash in the newspaper, recollecting the time he witnessed The Flash save Joe from The Mist. Henry then notes the coincidence of him recently being harmed by Julius and of The Flash extending Julius' prison sentence due to his breakout, comparing it to The Flash saving Joe, implying that he believes Barry is The Flash. Barry denies being The Flash, saying that Henry would have been the first to know. Henry then states that if The Flash were his son, that he'd first tell him that the world is dangerous and that he should be careful. Second, he would tell him that he is a hero who is saving many lives, and lastly that his father would be proud of him, leaving a teary-eyed Barry looking up at Henry.
Henry was later kidnapped by James Jesse, who wanted to use him and his connection to the CCPD as an bargain in case his plan failed. However, Barry ended up rescuing him at the last minute and subsequently confirmed his father's theory of him being the Flash by removing his mask.
He was cleared of murder charges after Barry was given a video of Reverse-Flash's confession to the murder of Nora. He was soon set free and, after a brief reunion, decided to leave Central City. However Henry came back when Barry got his back broken by Zoom and he got Barry to believe in himself again to be The Flash again which worked. Henry shortly then leaves again. Time passes and Barrry who had his speed stolen by Zoom goes visits Henry at his remote cabin in the mountains where Henry gets updated on Central City current events. Henry was bewildered when Barry told him that Jay Garrick was really Hunter Zolomon, aka Zoom, leaving Henry saying this his mother was a Garrick however Barry didn't ask for more elaboration from him about his paternal grandmother. Barry took his father back to the city where Henry decided to stay for good this time. After Team Flash's failed attempt to have Barry regain his powers Henry was distraught over the apparent loss of his son however he quickly pulled through to give medical attention to a comatose Jesse who was knocked out by a wave of energy. He was relived when Barry came back from the inter pocket dimension of the speed force. After Barry got his powers back, Henry became a member of Team Flash. While celebrating Henry's return, Zoom crashed the party and kidnapped him. Zoom then killed him in front of Barry, phasing his hand through his chest.
After Henry was accused of murder and arrested, Barry decided to devote his life to find his mother's real killer, knowing that Henry was innocent and became a forensic scientist in CCPD. It was also because of this event that Barry decided to become the Flash.
After his death by Hunter Zolomon, Henry was deeply mourned by Team Flash but his death affected his son the most. Barry struggled to forget his event and was at first successful. However when meeting Henry's doppelgänger, Barry's depression came right back. He looked back at the many losses he had in his life and decided to change the timeline in order to feel success and to rid him of his suffering.
Barry rewrote the timeline by stopping the Reverse-Flash from killing Nora in 2000. This prevented Henry from going to prison for murder.
Barry took Thawne, traveled to 2016, and set out to live a normal life, which included living with Henry and Nora. After three months of living with his parents, Henry and Nora tried to ask Barry to find an apartment. Barry seemed shocked and asked why they wanted him to move out. They said that they only wanted him to have his own place in case he got a girlfriend. He then told them that he has a date with Iris West.
After realizing that Flashpoint is worse for everyone else than the original timeline, Barry decides to reset what he'd done. Iris and Barry visited Henry and Nora in order for Barry to say one last goodbye to his family.
However, Barry had to reset the timeline back seeing how much his selfishness had caused everyone around him. Henry's fate in this timeline remains the same as before Barry created "Flashpoint", except the time of his death is unknown.
Henry was kind, caring, sympathetic, compassionate, selfless, and intelligent, he was a loving husband and father, as he loved his wife Nora very much. When the Reverse-Flash stabbed her in the heart with a knife, he did everything he could to save his wife. He was devastated by her death, and he loves and cares about his son Barry.
He used to be good friends with Joe West, until the latter chose to believe he was guilty of killing his wife. When Joe came to visit him, Henry was not happy to see him, partly because he did not visit him for 14 years, and mainly because he believed he was a murderer. Despite his anger towards Joe, when the latter was poisoned by Kyle Nimbus, he called a guard for help.
Joe and Henry eventually reconciled when Joe came in to tell Henry he now believes Henry is innocent and vowed to get him out sooner or later.
As some may expect, after multiple clues, Henry eventually discovered that Barry is indeed the Flash. However, when an incident in Iron Heights caused Henry to be stabbed, Barry immediately questioned his father for the name of the person who did it. He was surprised to hear that his father had assisted Joe with an investigation for the end-purpose of helping out Barry. Upon the resolution of the case, Henry held a photo of "the Flash" that Iris had caught, which was front-line paper (and it was a clear resolution photo), which showed his face, which Henry had seen twice. While it was never confirmed, by his exchange with Barry in a conversation about "what Henry would tell him" if the Flash were indeed his son, it was strongly hinted that Henry had put the pieces together.
Henry was also adamant in pertaining his son's life above his own, to be full and lively, as evidenced by his refusal to support Barry in going back in time to prevent his wife's murder. While Henry was indeed sad over this decision, at the prospect of regaining Nora, he reaffirmed to Barry that neither he "nor Nora would approve undoing history" to change the person Barry had become. Henry stated that he didn't want Barry's current growth to be undone by changing history. He even went to further state that while he was in awe of the man that which Barry had become, he also affirmed that Nora would have been equally proud and would also object to his plans to save her.
Henry could be considered someone who "gave up on" his own life, but not in a suicidal sense - He realized his son had a bigger purpose than him, largely because of the impact that, as "the Flash", had changed Central City, and may have eventually realized the full-scope of what he would or could become. Through this, Henry supports his son, and while he may not agree with his judgement, like going back to stop Eobard from killing Nora, his wife, Henry objected, but reaffirmed to his son why it was better. Henry has all but given up on getting out of jail, and even tried to persuade Barry from pursuing "the man in yellow", aka the Reverse Flash, throughout the first season. It could be argued that, while Henry now knows what Barry could do, he believes there was a natural order, and that with Henry being sentenced to life in prison, there was a reason he is in there, and, in some instances, it shows that Henry believes his "reason" for being in there, was for Barry.
Through this, Henry had accepted his wife's being gone, and had learned to live with it, but also learned to live "alone", in that he realizes he can't be apart of Barry's life, and while he wants to, badly, he wants Barry's life to be his own, and not allow Barry to undo his own growth for the sake of him or his wife.
Due to having a history with science from his path to being a doctor, Henry believes the natural order of things should not be interfered with. As a result, he protested against Barry going back in time to save Nora, even if it meant Henry would be able to raise Barry with his wife, and his lost honor as a doctor and innocent man would be restored.
- Expert medic: Henry was shown to be an expert in medical care, as he was a doctor for an unknown number of years before his wrongful incarceration, despite the fact that Henry was in prison for 15 years, his skills have not diminished.
- High-level intellect: Henry was very intelligent, he was able to put together a number of interactions with the Flash, as he figured out that he is Barry. This was also what allowed him to become an M.D.
- "Legends of Yesterday" (mentioned)
The Flash: Season Zero
- "A Captive Audience" (mentioned)
Behind the scenes
- In the DC comics, Henry was framed by Professor Zoom for Nora Allen's murder after Professor Zoom killed Nora. Also, Henry died in prison before his son Barry Allen had proved his father's innocence.
- John Wesley Shipp, Henry Allen's actor, played Barry Allen/The Flash and his clone Pollux in the 1990 series of the same name.
- It is revealed that Henry's mother's maiden name was Garrick. This is a reference to Jay Garrick, the Golden Age Flash. His Earth Three doppelgänger was later revealed to be Jay Garrick.