Christopher Gorham who was Katie’s character Trish Wellington fiance in Harper’s Island and who killed her in it, did a interview with Yahoo and talked about both the show and Katie in it.
Yahoo: How did the Harper’s Island role come to you?
CG: I was asked to come in and read for the role after the pilot had already been picked up to series. Katie Cassidy and I both joined the show this way, so they had to re-shoot every pilot scene we were in.Y: Since going off the air, the show has built a following via DVD and streaming — how often do fans still ask you about it? Are they still angry at you for killing Katie Cassidy?
CG: Most often people want to know if/when I knew I was the killer. And, yes, they’re all still angry. She’s fine, guys! She’s on Arrow!