The Flash has been a highly successful series for the CW Network over the past six seasons. In that time, audiences around the world have seen police forensic scientist Barry Allen become the titular hero and battle various villains, all the while supported by his family and close friends.

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However, while you may know all about Barry's life, some real-life secrets about the show are closely guarded, like a rogue metahuman in the pipeline. Read on for ten things about The Flash that you likely didn't already know.

Grant Gustin Shares Similarities With Two Other Cast Members

The lead role of Barry Allen is played by actor/singer Grant Gustin. Prior to this show, Gustin was best known for playing recurring antagonist Sebastian Smythe on Glee for the Fox Network. Now he has landed the role of a lifetime and it seems like it was always meant to be.

Like his co-stars Jesse L. Martin and John Wesley Shipp (who play his foster father and biological father/speedster mentor, respectively), Gustin was born in the state of Virginia during the month of January. Each of the three men's birthdays occurs four days apart. Grant Gustin's falls on the 14th, Martin's on the 18th and Shipp's on the 22nd. Finally, Gustin was born in 1990 — the same year Shipp began playing Barry Allen in the original live-action Flash television series.

John Wesley Shipp Made An Important Connection Two Decades Early... And Didn't Realize

For one season on CBS in 1990-1991, John Wesley Shipp played the part of Barry Allen/Flash. The series only lasted for twenty-two episodes. Until 2014, Shipp was the only actor to have played the Scarlet Speedster in a live-action television series.

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However, while promoting the new series at San Diego Comic-Con 2014, Shipp revealed an interesting piece of information. He had actually met future The Flash co-developer and now former showrunner, Andrew Kreisberg, as a younger man on the original series' lot during the early 1990s. Obviously, he had no idea that this person would one day give him a very important job in terms of his career.

Candice Patton & Danielle Nicolet Worked Together Before

Prior to playing reporter Iris West-Allen and District Attorney Cecile Horton, effectively stepdaughter/mother, Candice Patton and Danielle Nicolet had shared the small screen once before. This was a project completely unrelated to DC Comics.

Both women were recurring guest stars on the 2006-2015 BET series The Game with Patton playing Tori and Nicolet playing Yana. Each appeared in several episodes though their characters crossed paths in "Chardonnay Goes Kissing" in which the characters are involved in a confrontation. Not exactly motherly behavior.

Tom Cavanagh Accepted His Role For A Specific Reason

The Flash the Reverse-Flash uses his powers

Of the original regular cast on The Flash, former Ed star Tom Cavanagh was one of the best known. Now reinventing himself with a new role as Harrison Wells on The CW series. This show was the third collaboration between Cavanagh and producer Greg Berlanti, following Jack and Bobby and Eli Stone.

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However, Cavanagh has said in the past that he was uninterested in the role of Dr. Harrison Wells on its own. Upon being told his character's twist — that he was really Eobard Thawne/Reverse-Flash — sealed the deal in Cavanagh accepting the role, relishing the opportunity to play the iconic villain.

The Cast Includes Former College Classmates

Of course, an important component of acting is pretending to be a different person and thus, having experiences that are not the same as your own. For that reason, while characters on this show are meeting for the first time, the actors already know each other very well. There are two notable instances of this.

Grant Gustin attended Elon University in North Carolina alongside Supergirl actor Chris Wood, who formerly played Mon-El. Similarly, The Flash regular Carlos Valdes (Cisco Ramon) studied at the University of Michigan with guest star Darren Criss, who played Music Meister.

Barry And Iris' On-Screen Daughter Is Older Than Them... IRL

In season four, actress Jessica Parker Kennedy is introduced as Nora West-Allen, the daughter of Barry and Iris from the future. She also goes by her superhero name XS, hailing from approximately thirty years on from the events of season five. In Nora's time on the show, she formed close bonds with both her parents.

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In the context of  The Flash, having a similarly aged daughter was bizarre for the characters. The real-life situation, however, is even weirder. Jessica Parker Kennedy is older than both her on-screen parents, clocking in at four years older than Candice Patton and six years older than Grant Gustin.

Andy Mientus Originally Read For A Much Different Role

Andy Mientus in The Flash

Actor Andy Mientus has played the recurring role of Hartley Rathaway/Pied Piper since the first season. A disgruntled former Star Labs employee, Pied Piper has appeared as recently as the current sixth season. However, if Mientus' original intentions had gone to plan, he would be playing a very different role in the series.

Before being cast as Hartley, Mientus originally read for the series lead, The Flash himself, Barry Allen. Of course, that went role went to Grant Gustin, who has made it his own. At least Mientus still ended up on the show in any case.

Rick Cosnett Signed Up To Play Another Character

Rick Cosnett played Detective Eddie Thawne in the first season of The Flash, right up until the character's heroic sacrifice in the season finale. As an ancestor of Reverse-Flash, Eddie had the power to erase the villain from existence, once and for all. This effort, unfortunately, would cost the dedicated detective (and boyfriend to Iris West) his life.

In the original development of the series, Cosnett was set to play a completely different character — legendary DC hero Jay Garrick, the original Flash and Barry's mentor. Of course, these plans changed and the character was reworked into Eddie, with Garrick later being played by John Wesley Shipp.

Dominic Purcell Has An Old Co-Star To Thank For His Role

Dominic Purcell has played Mick Rory/Heat Wave in the Arrowverse for approximately five years. He originated the role as a villain on The Flash before joining the 2016 spin-off, Legends of Tomorrow, on which he continues to star.

In both shows, Purcell stars opposite his former Prison Break co-star/on-screen brother Wentworth Miller, who plays Leonard Snart/Captain Cold. Miller had been introduced on The Flash as Snart prior to Purcell's debut and recommended his former colleague as the man to play his on-screen partner-in-crime for the DC world.

Grant Gustin And Jessica Parker Kennedy Appeared Together On Another Show... Sort Of

One year prior to The Flash's debut on The CW, future on-screen father and daughter, Grant Gustin and Jessica Parker Kennedy appeared in the same episode of 90210, just not at the same time. At the time, Gustin had already appeared in Glee and CSI Miami while Kennedy was known for her roles in Smallville and The Secret Circle.

On 90210, Gustin played the role of Campbell Price for eight episodes. Kennedy, on the other hand, played Megan Rose for six episodes. Coincidentally, in their shared episode, "Here Comes Honey Bye Bye", Kennedy was finishing her stint and Gustin was debuting.

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