When Sendhil Ramamurthy was cast as one of the big bads for Season 6 of The Flash, Heroes fans everywhere rejoiced. Little did we know, though, that one of those fans was actually the show's star, Grant Gustin.

"I had seen all of Heroes — not maybe every season but most every season, I think — and then was really excited about his casting," Gustin told TV Guide on a recent visit to the show's set. "First of all, he's like an amazing guy, like bromance right away. And he's a really good actor. [His casting] definitely inspired me to go back and check [Heroes] out."

Gustin actually binge-watched the first season "in like five days or something," which is all the more impressive because it featured 23 episodes. "I was a little embarrassed coming and seeing him, looking at him work and being like, 'Yeah, I'm watching, like, everything! I just watched this episode, you were like pinned to the ceiling!'" Gustin said.

Everything We Know So Far About The Flash Season 6

Ramamurthy confirmed a fast friendship has formed between the two, even if their on-screen counterparts were mortal enemies. And it sounds like Gustin lived out every TV fan's dream: actually becoming besties with one of his favorite TV stars.

"That's been ... one of the coolest things [about joining the show], just getting to work with Grant," Ramamurthy said. "We've been getting along so well. I think our work ethics are very much the same. We're like super-focused and serious on set, but then as soon as the camera stops rolling we can just drop it and kind of mess around a little bit."

<p>Grant Gustin and Sendhil Ramamurthy, <em>The Flash</em> </p>

Grant Gustin and Sendhil Ramamurthy, The Flash

Messing around was probably necessary given the dark subject matter woven throughout Ramamurthy's villainous story arc this year, but there was one instance in particular in which both men recalled not being able to keep it together.

"[I] can't spoil too much, but literally [these] words come out of his mouth: "Save the world, blah blah blah," and all we're hearing is, 'Save the cheerleader, save the world,'" Gustin said. "To hear him say 'save the world,' like in my ear? You're like, 'Oh my god!' You get chills a little bit."

"There was a scene that we shot ... and 'cheerleader' was in the dialogue and we couldn't get through it," added Ramamurthy. "When I was saying it, I kept wanting to say, 'Save the cheerleader, save the world.' And you can't do that. But no, we were giggling through the whole thing."

We can just imagine these two messing up every take because they can't stop cracking up. And to think, they tell you to never meet your heroes. (Pun totally intended, obviously).

The Flash airs Tuesdays at 8/7c on The CW.

(Disclosure: TV Guide is owned by CBS Interactive, a division of CBS Corporation.)

<p>Grant Gustin and Sendhil Ramamurthy, <em>The Flash</em> </p>

Grant Gustin and Sendhil Ramamurthy, The Flash