Katie Cassidy was cast as Laurel Lance on "Arrow" in the spring of 2012 and fans of the comic immediately went, "So she's Black Canary."

It took three years, however, for Cassidy and Laurel to finally take on the mantle of Black Canary.

There was a first season that pushed Laurel to emotional extremes, but not into the costume of a masked vigilante.

There was a second season that included more emotional extremes, but when Black Canary was introduced, it was Laurel's sister Sara (Caity Lotz) taking on the bad guys.

It's only been in Season 3 that Cassidy and Laurel have achieved their Black Canary destiny, which Cassidy calls "the coolest thing ever."

"I've waited for so long for this and, honestly, I think that it was done in the right way," Cassidy told me on the PaleyFest 2015 purple carpet over the weekend. "We didn't do it too soon and I feel that Laurel really had to earn becoming this superhero. You can't just, all of a sudden overnight, wake up and be able to do it."

In the interview, featured above, Cassidy admits that she was sold on "Arrow" with the potential of becoming Black Canary and that the waiting wasn't always easy. She also talks about how Black Canary works as an outlet for some of the anger inside Laurel and that her addictive personality will continue to be relevant.

And has she started complaining about the Black Canary suit yet?

Check out the full Katie Cassidy interview above. And don't forget to watch my Emily Bett Rickards interview delving into Felicity's Jewishness.

"Arrow" returns to The CW tonight (March 18).

A long-time member of the TCA Board and a longer-time blogger of "American Idol," Dan Fienberg writes about TV, except for when he writes about movies or sometimes writes about the Red Sox. But never music. He would sound stupid talking about music.