Playing Superman, or Supergirl, is one of those roles stays with an actor throughout their career. Whatever else they might do, whatever else they achieve, their connection to Krypton will always be there in the popular imagination, and it will likely be a topic in every interview they give.

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Having portrayed the Man of Steel on the 1990s TV series "Lois & Clark: The New Adventures of Superman," Dean Cain is fully aware of the weight of the role. Now appearing on The CW's "Supergirl" as Jeremiah Danvers, the adoptive father of Kara, the 50-year-old actor revealed what he views as the key quality for playing such an iconic superhero.

"Kindness. First and foremost, it's kindness." he told Moviefone. "You're the most powerful being on Earth, or one of the most powerful beings on Earth, and you have to have a kindness, an ability to relate to everyone, and that's what Superman or Supergirl does."

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"They say the 'S' means 'hope,' and that's a great thing, but Superman is always kind," he continued. "Obviously, if he's fighting a foe, he'll fight him until he's got him beat, but then he would pick him up. It's been tougher with the latest incarnations, but I think kindness is about the most important thing," the actor added.

Airing Mondays at 8 pm ET/PT on The CW. "Supergirl" stars Melissa Benoist as the Girl of Steel, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers, Jeremy Jordan as Winn Schott, David Harewood as Martian Manhunter and Chris Wood as Mon-El.