We know who killed Lilly Kane. We know who crashed the school bus. We know who murdered the Dean and the identity of the Heart College serial rapist. But there's one question still plaguing Veronica Mars fans: What the frak happened to Duncan Kane?!

Teddy Dunn was a core cast member for the first half of ofVeronica Mars' run -- until he was abruptly written off and never directly acknowledged in the series again. But now that Veronica Mars is experiencing a renaissance — not to mention its 10th anniversary — the questions surrounding Dunn's exit have resurfaced.

"It's funny 'cause with the movie and all the other stuff that's been coming out ... people have asked me about it and I talk about it. It's a good ice breaker, for sure," Dunn tells TVGuide.com. "So it's not exactly been out of sight out of mind, but it's definitely pretty far back in the past for me. I've gone with a different direction in my life and a different career."

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Now, for the first time since leaving the show, Dunn opens up about his experience playing Duncan, his feelings about getting written off the series, whether he'll ever return to Veronica Mars and more.

Dunn initially turned down Veronica Mars: After failing to get the part of Logan, Dunn was approached about reading for Duncan, but his representatives advised him to turn it down. "He only had five lines in the whole [pilot] and we weren't really sure where it was going to go," Dunn explains. "So they were telling me to pass and I did, like, two or three times I think." But creator Rob Thomas wouldn't back down and called up Dunn personally to explain who he envisioned Duncan being and convinced him to screen test for the role.

Dunn eventually landed the part, but despite the impressive cast and script, he had his doubts regarding the show's potential. "This is no knock on the network, but UPN wasn't the greatest network at the time. It has since folded or merged. So that alone wasn't the greatest selling point, especially when you go out for a show on Fox or NBC. The O.C. was on at the time and there were like 30 million watching that every week. So you're like, 'Okay, UPN. Does anybody even watch that?' Turns out some people do."

The real reason Duncan was so catatonic early in Season 1:Almost as soon as Veronica Mars premiered, it became clear that fans didn't like Duncan, who was originally slated to be Veronica's OTP. He came off as vacant, distant and just sort of... there. Duncan later became much more dynamic, but this isn't because Dunn's talent improved exponentially overnight. It's because Dunn was originally under the impression Duncan had a mental illness.

"I was told early on that Duncan was bipolar, so when I got the role I got some books, starting researching it and looking into it," Dunn says. Since psychosomatic drugs used to treat bipolar disorder often leave the user emotionally distant, Dunn made the conscious choice to play Duncan that way. However, once it became clear that viewers were having a hard time connecting to Duncan, "I was told to leave all that behind and go back to being the gregarious big man on campus," Dunn says. "I had a hard time reconciling the two and I think I struggled with the precedent we had set with the character in the first few episodes versus what they wanted to get out of the character later down the line.

"I understand there's a commercial aspect to it too, he continues. "You know, just this comatose brooding dude in every episode of your show. I get it. That was something that they don't teach you in acting school, you know? Just the sheer business side of it."

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What it was like when the fandom turned on him: While Television Without Pity was alight with fans hating on Duncan, Dunn never got the chance to explain what his intentions with his performance were. "No one ever asked me. I don't know if anyone ever asked what was going on with my character. If they asked Rob or someone else, I wasn't aware of it," Dunn says.

Despite this disinterest — and often outright dislike — for Duncan, Dunn did his best to stay above the fray. "Obviously, I acted because I wanted the fans to like the experience. You want your performance to be liked. You don't want to suck. You don't want people to think you suck. That wasn't the goal," Dunn says. "Once it's in the can, what are you going to do? People don't like it, they don't like it ... I wasn't really too worried about criticism other than if it was coming from my bosses."