Team Flash suffered a major loss in the Season 3 finale. After they successfully rescued Iris from Savitar, Barry sacrificed himself to the Speed Force to restore its equilibrium and save Central City. As such, when Season 4 picks up, the team will have been operating without him for a full six months. At Comic-Con International in San Diego, Candice Patton (Iris West), Jesse L. Martin (Joe West), Keiynan Lonsdale (Wally West) and Carlos Valdes (Cisco Ramon) explained how their individual characters have coped with Barry's absence since he disappeared six months prior.

"Six months in the future, [Iris has] kind of had to step into the role that Barry left and it's a kind of a way for her of distracting herself, too," Patton revealed. "She's obviously depressed and sad that Barry's gone and not sure when he's going to come back, so it's a good distraction for her to be the leader."

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"I think everyone is questioning if and when Barry is going to come back, and she deals with that in her own way," she continued. "I think you'll see a very, very, very different Iris picking up Season 4. She's almost hardened and a little more pessimistic and just kind of like, 'Gotta move forward. We gotta just keep moving. We don't know if Barry's coming back; we can't deal with that. All we can deal with is protecting the city.'"

As to Barry's life-changing decision, she said, "You know, he didn't consult her. It was a snap decision. So, I think, when and if he comes out, that's a conversation they need to have about communication. As iconic as they are, Barry and Iris still have their issues, and they desperately need to work those out before walk down the aisle. So that's something that I think we'll delve into this season."

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Asked what event has taken the greatest toll on Joe West, Martin responded, "I would definitely say Barry going back into the Speed Force, because it came out of nowhere and we didn't see it coming. Suddenly, we're just like, 'Wait a minute! We're losing you? Just like that? We don't get a warning or anything?' We spent the whole season last year trying to save Iris, and right after we save her, Barry leaves. I think that was the most devastating thing."

Joe will be "devastated, and also worried about the gang that is still there, particularly Wally and Iris. Like, Iris lost her fiancé, and he's very concerned about how she's taking it all in. Wally has to step up and be the Flash, if you will, along with Cisco's Vibe, and we're all still dealing with metas in Central City, so we have to keep up appearances, but the Flash is definitely missed. So I'm doing a lot of emotional repairing, if you will, to start."

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The Flash Barry Iris

"I mean, it's obviously devastating, but it's the theme of the show, right?" he added with a laugh. "It's been like four seasons now and anybody I love is going to get snatched up, challenged, thrown across the room, whatever. So it's going to be a constant worry for Joe. I'm always going to be in a position where I'm like, 'I need to help my kid' or 'I need to find my kid' or, like, 'I need to shoot this guy because he's messing with my kid.'"

Despite the emotional toll of Barry's sacrifice, Season 4 will find Wally coming into his own. "Wally is actually in a pretty good place! The whole team has had to step up and become a unit, and it's just like sort of becoming this sort of well-oiled machine, as much as they can without Barry," Lonsdale explained. "Kid Flash has like found his place and I think he's been forced to grow up a lot more. He is enjoying that freedom and independence that he has. Even if he's making mistakes, he's finding the light in it, which is cool."

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Nevertheless, "I think he's suffering like everyone, in a different way, but at the same time, he definitely has faith that he'll come back, so I think he's okay with that, but he's more so feeling for Iris and knowing how that's the closest thing to home is for her. He knows that she would be struggling the most, so I think he's caring less about his own feelings and more about hers," he said.

Joe West

Valdes had a different perspective on where Team Flash is at when things pick up in Season 4. "I can tell you straight up! It's not good," he revealed. "Six months have passed since the disappearance of Barry Allen, and the team is sort of clutching at straws to keep the city together. Although Kid Flash and Vibe are out in the field doing their thing and trying to keep it together, there is a unanimous feeling amongst the remaining members of the team that it is just not the same without Barry. We cannot keep the villains at bay with the same efficiency that he used to. So, in light of that, Cisco does whatever it takes to get his friends back."

Starring Grant Gustin as the Scarlet Speedster, The Flash returns Tuesday, October 10 at 8 p.m. ET/PT on The CW. The series also stars Jesse L. Martin, Tom Cavanagh, Carlos Valdes, Candice Patton, Danielle Panabaker, Keiynan Lonsdale and more.