How well do you know the Flash? Do you know who the first person was to learn his secret identity? When does Barry Allen celebrate his birthday? What is the hero’s greatest allergy?

With the Flash racing onto the big screen, now is a great time to brush up on your Flash Facts. From his secret family history to his superhero stats, here are some fun pieces of trivia on the Scarlet Speedster.

• Barry Allen was introduced in 1956’s Showcase #4. His original career as the Flash lasted 29 years in publishing time, until his death in 1985’s Crisis on Infinite Earths #8. Barry was then presumed dead for 23 years until his return in 2008’s Final Crisis #2.
• Barry Allen’s first use of time travel occurred in 1956’s Showcase #4. Using his super speed, the Flash broke through the time barrier to return a villain named Madzen to the 50^th century. Flash got started on his timeline shenanigans early!
• In 1967’s The Flash #167, an alien named Mopee claimed that he had given Barry his powers by directing the lightning bolt to hit him. Should we believe him? Probably not. 1988’s Secret Origins Annual #2 presented the idea that Barry had created a paradox by going back in time and becoming the lightning bolt that gave him his powers. This concept was reinforced in 2009’s The Flash: Rebirth. Given Barry’s love of creating timeline headaches, this makes more sense.

• Of course, Barry is not the first hero to call himself the Flash. Barry’s predecessor, Jay Garrick, originated the role in 1940’s Flash Comics #1. According to Showcase #4, Barry was a fan of Jay’s comic series. As a result, it caught him by surprise to learn that Jay was a real person when they met in 1961’s The Flash #123.
• Jay’s superhero name isn’t the only thing Barry took over. When Barry was given his own series (The Flash), it continued the numbering from Jay’s comic series (Flash Comics). As such, Jay’s series ended in 1949 with Flash Comics #104, while Barry’s series began in 1959 with The Flash #105.

• Who was the first superhero that Flash teamed up with? It depends on how you look at it. The Flash joined the Justice League in 1960’s The Brave and the Bold #28, which was the first time he was seen alongside other DC heroes. Kid Flash was introduced in 1959’s The Flash #110, but if you don’t want to count kid sidekicks, then his first one-on-one adventure with another superhero was 1960’s The Flash #112, which featured the first appearance of the Elongated Man. If you’re looking for his first team-up with an established hero, that would be Jay Garrick in 1961’s The Flash #123. If you’re really picky and want a non-Flash superhero, that would be Hal Jordan in 1962’s Green Lantern #13.
• Achoo! Flash is allergic to wisteria. His allergy is so severe that he’s unable to use his speed when he encounters the plant, as established in 1967’s Justice League of America #56.

• Wally West was the first person to learn Barry Allen’s secret identity. Although Kid Flash had been working with Flash since his first appearance in The Flash #110, Barry did not reveal his secret identity until 1961’s The Flash #120. At the time, the two were preparing to join Iris and some friends on a yacht and Barry wanted Wally to be aware in case danger happened while they were in closed quarters at sea.
• After the Flash’s heroic sacrifice in Crisis on Infinite Earths, his identity was revealed to the world. According to 2002’s Green Arrow #17, the curators at the Flash Museum blew the secret a few months after his death when they opened a new exhibit on the speedster’s life. In 2003’s The Flash #200, the Spectre caused the whole world to forget that Wally West was the Flash. This spell had a ripple effect, causing Barry’s identity to be forgotten as well. As a result, Barry Allen was able to enjoy his privacy when he returned from the dead during Final Crisis.

• Iris wrote a biography about Barry. It was published during the period when Barry was believed dead and his identity was public. The best part is, you can actually read it on DC UNIVERSE INFINITE (The Life Story of the Flash).
• Do you want to celebrate Barry Allen’s birthday? Good luck figuring out when it is. The 1976 DC Comics Calendar has it listed as March 19^th. However, in The Life Story of the Flash, Iris wrote that Barry was born on May 13^th. Can we blame this on Barry’s time traveling?

• Barry and Iris have twin children named Don and Dawn Allen. The twins became superheroes, calling themselves the Tornado Twins in Adventure Comics #373. They spent some time with the Legion of Super-Heroes before being killed in 1991’s Legion of Super-Heroes #17.
• Barry and Iris are also grandparents! Jenni Ognats (daughter of Dawn Allen) was introduced in Legionnaires #0. She operates as the heroine XS. Bart Allen (son of Don Allen) was introduced in 1994’s The Flash #92. He operates as the hero Impulse. Thanks to some time travel shenanigans, the Tornado Twins and their offspring were born and raised in the 30^th century. This explains why Barry and Iris look so spry for grandparents.

• Races between Superman and the Flash are a time-honored DC Universe tradition. The first one occurred in 1967’s Superman #199 and ended in a tie. According to a breakdown by DC.com’s Alex Jaffe, Flash has won three races, Superman has won two, and three of them ended in a tie.
• The Flash has a twin brother who is also a speedster. The existence of Barry Allen’s twin was first mentioned in The Life Story of the Flash and teased again in Flash Secret Files and Origins #1. 1998’s The Flash #144 revealed that the twins were separated at birth, with a doctor telling the Allens that one of their kids had died in childbirth. Barry’s brother Malcolm Thawne (yes, Thawne) grew up resentful of his twin brother. Thanks to a magical talisman, Malcolm was able to gain speed powers and become the villainous Cobalt Blue.

• It’s indisputable that Iris West is the love of Flash’s life, but she isn’t the only woman Barry’s been involved. During a period when he thought Iris was dead, Barry almost married his neighbor Fiona Webb. Unfortunately, a battle with the Reverse-Flash prevented the groom from attending the wedding (The Flash #324).
• As Wally West recounts in 1989’s The Flash #30, Barry insisted on being late for everything in order to throw people off his secret identity. Wally estimated that Barry missed the beginning of every movie he saw for over a decade.
   

The Flash is in theaters this weekend, and unless you have a secret identity to protect, you won’t want to miss a minute. So, race to your theater and get ready for an action-packed thrill ride through the depths of the Multiverse. You’ll have a great time…and that’s a Flash Fact!
 

The Flash, directed by Andy Muschietti and starring Ezra Miller as Barry Allen, is in theaters June 16th. Visit our official Flash hub for more news, interviews and videos about the Flash!

Joshua Lapin-Bertone writes about TV, movies and comics for DC.com, is a regular contributor to the Couch Club and writes our monthly Batman column, "Gotham Gazette." Follow him on Twitter at @TBUJosh.