Grant Gustin revealed at the San Diego Comic-Con 2016 why Barry had to go back in time in "The Flash" season 2 finale.

It can be recalled that the season 2 finale saw Barry go back in time to save his mother. This event is expected to greatly impact the upcoming season of the DC series.

The first episode of "The Flash" season 3 is "Flashpoint," which fans may easily recognize as the same DC Comics storyline.

Talking about Barry's time travel at the San Diego Comic-Con, actor Grant Gustin told IMDb, "People were like, 'Why did he do that?' And I think that he wasn't going to do that, but I think that sitting on that porch, having just defeated Zoom, Iris says to Barry what he's always wanted to hear, and he feels empty inside."

Gustin also had something to say to those who think it was too selfish of Barry to want his parents.

"That was the moment. As selfish as it was that Barry wanted his parents, I think it's more about these two speedsters took away their life because of me and they deserve to have a chance at life. I can't do this, I need to give them that chance," he added.

Gustin also revealed that none of the first few scripts of "The Flash" season 3 have made any mention of Kara Danvers.

"It's pretty Flashpoint focused right now, which I think we are going to see the repercussions coming out of Flashpoint. There will be ramifications all season long from Flashpoint."

The actor said that season 3 will not be all about Flashpoint.

"I think we can state Flashpoint does not last all season long," he noted.

"The Flash" season 3 premieres on October 4 on The CW.