It's official: the fun is coming back to The Flash in a big way for season 4.

Speaking to Digital Spy at San Diego Comic-Con, series star Grant Gustin admitted that the previous season might've gone a little too dark.

The third season of the superhero caper saw Barry (Gustin) pitted against Savitar, his own evil doppelganger, who appeared to murder Barry's beloved Iris (Candice Patton) in a chilling flashforward.

The CW

Gustin explained: "It was episode 9 or 10 that Barry saw Iris die in the future and then, for the rest of the season, it was this thing – Iris is gonna die – so even if it was just sub-text that was something that I, as an actor, had to deal with and play.

"So all of the scenes were dark, even when they were fun scenes, and it takes a toll on you. You go home in a bad mood, an agitated mood. You have more fun when you're having fun on-set and doing comedy... and we're gonna get back to that a little bit."

He continued: "Last year was... I don't know if it was darker than we meant to get, but it got pretty dark. This year, we'll be back to our roots."

In fact, Gustin said that season 4 of The Flash is most similar in tone to the very first season: "We've all come really far as actors... so I think we're going to be able to execute everything that we're being given more successfully than we did initially in season one, but it's going to be like that tone of season one.

"We're gonna get that fun, and get back to the comedy of The Flash. It's gonna be great."

Almost certainly helping to bring the laughs will be DC hero – and new cast addition – Ralph Dibny, the Elongated Man, who'll be an ally to Team Flash in their battle against new foe The Thinker (Neil Sandilands).

The Flash returns Tuesday, October 10 at 8pm ET on The CW in the US. Sky 1 airs the show in the UK.

Want up-to-the-minute entertainment news and features? Just hit 'Like' on our Digital Spy Facebook page and 'Follow' on our @digitalspy Twitter account and you're all set.

This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.io