Longtime fans were excited when they learned John Wesley Shipp, who starred in the title role of CBS' 1990-1991 "The Flash" TV series, would play a part in The CW incarnation. But it wasn't just in a wink-wink cameo -- Shipp was cast as Henry Allen, the father of lead character The Flash/Barry Allen (Grant Gustin). It's a recurring role, and also a pivotal one -- the mystery behind the death of Barry's mother, Nora, has propelled the entire first season, with Henry wrongfully imprisoned for the crime.

Up until this point, Shipp's scenes have been somewhat limited by nature, given that he's behind bars -- mainly phone conversations with his son, with a glass partition between them. That looks to change in tonight's episode, "Crazy for You," written by Aaron Helbing & Todd Helbing and directed by Rob Hardy. In the episode, Joe West (Jesse L. Martin) -- recently convinced of Henry's innocence -- enlists Henry's help in an investigation, a partnership that doesn't go over well with Henry's fellow inmates.

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CBR News spoke with Shipp about returning to "The Flash" world more than two decades after he himself donned the iconic scarlet uniform, the return of fellow original series cast members Amanda Pays and Mark Hamill and what that says about the current show. We also dig into his considerably more active role in tonight's episode and the explosion of comic book-based live-action TV series in recent years.

CBR News: John, before we get into the particulars of this week's episode, I wanted to talk about your overall experience getting back into the world of "The Flash." Since the original series, you've certainly had a lot of different roles, but was "The Flash" always something you fondly remembered, and looked back on in the interim 20-plus years?

John Wesley Shipp: It was a seminal moment in my career. I had been on the East coast, and I had done a lot of daytime -- of course, I had my two Emmys, which I'm proud of. Shameless in bringing that up. [Laughs] And I had been on Broadway. "The Flash" represented my jump to prime time -- and what a way to jump, in the most expensive show Warner Bros. had ever done. We had a third of the backlot at Warner Bros. that year. To know that I had a place on that lot was very exciting.

Having said that, it was the hardest thing I could ever imagine doing. When I saw Grant at the third episode, I went up to him and said, "Has it gotten real yet?" [Laughs] Anyone who plays a costumed character knows that you're essentially playing two parts. You're essentially in every scene, and the weight of that is really challenging. If you care, it can be challenging emotionally. At any rate, it's beyond difficult, physically. I really do feel like I'm a member of a -- it can't be a fraternity, because there are women [who do comic book roles] -- a "frorority" of people who have done that, and lived to tell about it.

You're also not the only actor from the original show that's been a part of the current series -- Amanda Pays returned as Tina McGee, and Mark Hamill will play The Trickster in an upcoming episode. That's the kind of thing that doesn't always happen, as subsequent incarnations often want to run from the past. This show, however, has embraced it. How gratifying is that for you, to know what you did almost 25 years ago had such an impact on the creative people running this version of The Flash?

I think there are two reasons for that. Number one, all of our executive producers were fans. They make no bones about the fact that they were big fans of the first effort. When I met Andrew Kreisberg, he said, "We've already met, I was an assistant on the backlot of Warner Bros. when you were doing 'original Flash.' I totally came up and invaded your space and fanboy-ed out on you." I knew right away that they watched the show. Although Greg Berlanti, when we were doing "Dawson's Creek" together, he never mentioned it, and I found out that The Flash was his favorite character. David Nutter said, "You know, you were my hero growing up." They watched the first effort carefully.

The fact that they are willing to bring in elements from the previous show is a sign of some really secure creators. Creators who are so secure in what they're doing, and the newness and the freshness and the moment behind what they're doing, that they're not afraid to bring elements from the past as homages and integrating them into their vision for the present and for the future. To me, that says we've got some executive producers who are very secure in what they're doing today.

There had only been a handful of live-action comic book-based TV shows when you were doing the original "Flash," and now there's so many on TV, and so many more in development that we're hearing news about every day. What's it like for you to see that evolve and become a big part of television -- something you were involved in 25 years ago?

When we all went to San Diego Comic-Con, this last fall, Jesse Martin was amazed. He was like a kid in a candy store. "Oh my God, we're getting all this love coming at us." We premiered our pilot in front of 7,000 people, we were oversold in Hall H. He was like, "We haven't even been on the air yet!" It's like we were walking into an audience that is there waiting for us. That wasn't true in 1990. We certainly had the niche audience that were the hardcore comic book fans that were very excited about us being there, but we weren't stepping into a mass audience. Comic books hadn't yet gone mainstream, so to speak, in the way that they have now.

The comic book sensibility and the comic book craze, I think we're sort of at a peak of that in a way that wasn't true 24 years ago. You're walking into an audience that is sitting there waiting to receive you, instead of trying to convince people that may not be comic book fans that you're worth watching. That's a very different dynamic.

Thus far, viewers have seen your character in a limited capacity, given that he's imprisoned. It sounds like here he's taking on a more active role -- what can you share about your part in this week's episode?

What's been interesting so far is that Henry's had one window on the world, through the glass of the prison, and also metaphorically -- his one contact with the outside world is his son, the only one that believes he's innocent. Everybody else, including his friend Joe, who's raised his son, is hammering into Barry's head, "Your father's guilty, he's paying for what he did." Then Joe discovers [the truth], and we have that slightly contentious scene where we make our peace.

In this episode, it moves beyond that, where Joe and Henry -- unbeknownst to Barry -- enter into, and I can't tell you how, some kind of partnership with Henry on the inside and Joe on the outside. Barry's reaction to that, both no longer being Henry's only access to the outside world, but also concern about his father's well-being, is very interesting to watch. Also, as a result of getting roughed up, I get out from behind the glass partition. It's very interesting, and I don't think it's an accident that's also the episode in which I'm the in infirmary and Barry's right there, and we have no glass between us, as a metaphor for separation. We deal with the issue -- does the father recognize the son? Does Henry know that Barry's The Flash? And if he does, would he say so, or would he open a door for Barry to tell him? And if he does, would Barry tell him? Those are questions that we deal with in the episode tomorrow.

It's a very special one for me. I suddenly have more than one window on the outside world, and I'm having physical contact with more than one character; not sitting in a chair, talking on the phone. As wonderful for may those scenes have been, it is fun, now, to take him to the next level.

Right, there's an inherent limitation in those scenes behind the glass -- what kind of challenge is that for an actor? You're physically limited but still conveying a range of emotion.

As an actor, it behooves you not to look at the limitations, but to look at the advantages. The advantages are that we can't move. We are in the chairs. We are talking on a phone that is connected to a wall. There's not a lot of busy-ness that we can do. That means that Grant and I have to throw our attention on each other, and we have to make it about not the words that we're saying, but an expression that flickers across his face. When he gets emotional, how I react what he may do differently take by take, and how wonderfully he responds when I do something a little different. Even though the lines stay the same, there's a degree of improv, because we're thrown onto our something. We can't physicalize it -- it all has to be heart to heart.

That's a wonderful advantage, in that the limitation forces us to go in that direction. I believe that's why those scenes, in the middle of a show that moves so fast, have been so effective. It gives the audience a chance to breathe and to look at these faces and these hearts of these two men, and get involved with this father-son relationship. It's just excruciatingly poignant.

As one of a very small number of people in the world to have the experience of playing Barry Allen, what are your thoughts on what Grant Gustin has brought to the role so far?

I'm approaching this role as a standalone role. I wouldn't very much have enjoyed doing a cameo and walk through. The fact that Geoff Johns has created a much different and much darker backstory for Barry, and that this Henry Allen and Nora Allen story is very different -- it's a standalone character. When I stop and think about it, I realize that he's playing the same character, but there are significant differences. Number one, it's much more youthful -- he's 10 years younger than I was when I was playing Barry. Number two, the suit is different. He is what I thought we should have been more in 1990 -- he's much more aerodynamic. Since the guy's thing is speed, it would make sense that he would be aerodynamic. The suit reflects a more urban, contemporary sensibility.

People say, is it familiar? Yeah, in the sense that you walk up to a familiar house, and you open the door, and all the furnishings and all the rooms are completely different. It's not really revisiting something, as recreating a universe that I was once a part of.

"Crazy for You," the latest episode of "The Flash," airs 8 p.m. Tuesday, Feb. 3 on The CW.