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.

We often ask, "Do we have enough humans?" Because it's always fun to come up with an animal in show, but it begins to feel like overkill.

One of the things I've found really interesting about the show is that a lot of people really relate to our animal characters, more than we thought they would. Part of that is, because they are animals, people project themselves onto them. If BoJack just looks like Will Arnett, people go, "Oh, I know who that guy is. That's a Will Arnett type." But because he's a horse, people can go, "Oh, I'm kind of like him in some ways."

BoJack especially is a very dialogue based show. A lot of the comedy comes from conversations, and a lot of story comes from misunderstandings and people trying to connect with each other, and there was a really interesting challenge trying to write a script with no dialogue.

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?"

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.

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."