In "When Harry Met Harry," this week's episode of The Flash, Harry will summon the Council of Wells, "a roundtable of the brightest Harrison Wells’ from various Earths." Of course, when it comes to Harrison Wells and his many doppelgangers, there's only one man behind the various roles: Tom Cavanagh. During a set visit, Cavanagh offered some insight into how he played so many different roles in one scene, teased what versions of Wells we can expect to see (and one we won't) and more.

"This show will come and run its course -- or it will be like Supernatural and never end -- and, then it will all be done, but at least we will have this stamp of shamelessness. With the Council of Wells, I will always be able to point to that and go, 'Look at this exercise in egotism that we managed to pull off,'" he said with a laugh. "Unfortunately, for Brent Crowell, who is our production manager, it was his first time directing this show. He got saddled with having to tolerate me not playing just one character, or two characters which I normally do, but playing a multitude of characters, each one worse than the next. But, only if you line them up that way."

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Asked what went into creating all of these different personalities, he continued, "I remember Steve Van Zandt saying that Bruce Springsteen always has a number of songs in the scrapbook, ready to go. Steve’s quote was, 'It’s really annoying.' I’m that way with characters. I have a number of them. It’s just a question of, 'Well, do we want ten? Do we want two?'"

"We had a number of them at first," he explained. "I was like, 'Listen, the show The Flash should be about the Flash, and not about Wells. So, what will happen is if we do ten, we will end up cutting all their stuff because we can only really afford to have three or four scenes in this arc. We thought it best that we pare it down. We went from ten to six to four, or so. And, so, I think it’s unfortunate the Russian didn’t see the light of day. But, if this show keeps going, there will be plenty of time."

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"I had a bunch of those ready last year when we searched for H.R. I threw the steampunk guy, and the mime guy, and Hells Well, the Texan. Once again, another exercise in shamelessness that went so well that we decided to expand. Business is booming when it comes to the Wells. This year, I pulled out the ones that I wanted to at least get out there right now, but we have plenty more in the pocket," he said.

"When I do different characters on the show, my goal is to try and fill gaps that we have, and openings we have on the show. So, in the first year, we didn’t have a daily antagonist. We had the main, overarching antagonist, which was the Reverse Flash, which I played. In the second year, we didn’t really have that as much, at least not a comic-book regular the way the Reverse Flash is. So, I introduced Harry, who is kind of socially awkward and difficult and antagonist, but ultimately a good guy at heart," he recalled. "At least it had some grit and conflict in our daily rapport and within the cortex in STAR Labs and so on and so forth. They made it nice for someone to be antagonizing Snow and Ramone. Then, in the third season, I thought we could do a little more comedy here, so HR was created."

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"These other guys, when I create them, I try and do guys that are a little bit different." With a German accent, he said, "'You had this guy that thinks everything that is not German is not good.' That’s him... Then, the Australian, who is just a bad ass from the Outback, who doesn’t like anybody... I felt it was best if 'he spoke like that,'" he added with an Australian accent. "That was sort of it and then, they play off each other. I could do that all day and did do it all day."

"Unfortunately, one of the casualties was Wells the Gray, who was a Gandolf guy basically throwing out nonsequiturs. But, it was more to my liking than to a television show like The Flash. All that stuff ended up on the cutting room floor, which we thought it would. There’s room for Wells the Gray down the line, in Season 17, when I really will be gray."

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Carlos Valdes, who plays Harry's frenemy Cisco Ramon, also weighed in on the scene. "It was almost too much, you know. It was a very overwhelming process," he shared. "Obviously, Tom is very good at riffing on this particular character and letting us see different shades of Wells, but this just goes so over the top in such a gratifying way. Yeah, it's almost too much to handle, you know, because when we shoot different versions, actors being different versions of the same character, it takes time. You gotta get into the makeup, any sort of prosthetic or costumes and stuff like that. That takes time. You do the take with Tom, and there's stand-ins standing in for the other versions of Tom. And then once you do that coverage, you've got to wait 40 minutes for Tom to get processed into another character, and then you shoot that coverage, and then you do that five times, you know. So you have to keep that tiny scene fresh in your mind for hours while you get all that done. But I'll say this: For as long as it took, he sure made it a lot of fun, just constantly improvising and riffing. I think people will dig it a lot."

"It's always fun to work with Tom Cavanagh in whatever. I didn't get to work with him in I think what this is if I remember correctly. I heard about it. The crew was blown away. He always impresses. He's a legend," added The Flash himself Grant Gustin.

Starring Grant Gustin as the Scarlet Speedster, The Flash airs Tuesdays 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.