I think it's good to leave people with the memory of that being a great character. And if we have a reason to bring him back, we'll bring him back.

It was fun figuring out the science of the world as much as we wanted to figure out, and then playing fast and loose in other places. Which we do with our show in general. One of the things we love about the BoJack Horseman show is that we can always fall back on, "It's a ridiculous cartoon." And it is! It's a serious, relationship-based grounded character tragedy, but it is also a ridiculous cartoon.

I think you can imagine everyone has ankle weights on, or technology, and there's a reason that people aren't floating around. But I also liked this idea that in this world, people forgot they can swim. The modern world weighs you down, there's always emails to check, you've gotta go to your job and pay your mortgage. You're not really thinking, "Oh, yeah, I can swim around." BoJack discovering it is a big deal, and kind of fun.

I want each season to feel new and special. I don't want it to feel, "Oh, more of this." That's something that's easy to do in the first three seasons, and harder to do as you go. I'd rather err on the side of blowing up everything and being like, "Why did you do that? There was more story to tell there," and moving the family to Mexico like on Weeds, instead of people going, "Oh, we've seen this already. We're tired of this."

It's really cool to get these guests on the show BoJack Horseman: not just actors, but, "Can I get Jonathan Lethem on my weird talking horse cartoon show to talk about how growing up in Brooklyn, he always dreamed of being a ringtone?"

Daniel Radcliffe was actually a fan of the show and excited to be on it. Some of it is we've gone long enough that we're legitimate. Even if they don't know the show, they know we are a show and not some weird thing that's going to go away. Also, the more celebrities we get on BoJack show, the more it feels like a club to be in: "If Naomi Watts will make a fool of herself, I guess I can make a fool of myself, too."

That's part of the comedy, too, is we do have jokes throughout of hanging a lantern on the absurdity of the world. Like, when BoJack's flying over the neighborhood, you see some houses have swimming pools in the backyard, and what does that mean? Why would there be a swimming pool underwater? But we thought it was funny.