From Whoopi Goldberg to Jonah Hill, HBO’s "Animals" will be crawling with guest actors going into Season 2.

In just a few short years, Phil Matarese and Mike Luciano have gone from working at an ad agency in New York to writing about the animals that live in New York on HBO’s “Animals.” At their panel at SXSW this year, moderated by IndieWire’s Eric Kohn and accompanied by producer Jen Roskind, the three of them detailed how a small independent pilot managed to get picked up by HBO. They also offered some sneak peeks into what the unpredictable series has to offer, going into Season 2.

When the first episode was created, with only Matarese and Luciano on board hoping to turn it into a full-fledged web series, screenings of “Animals” was kept exclusively to small crowds in and around their native New York. After being featured at a festival though, they were found by the Duplass brothers, who decided to go ahead and fund the show independently. They managed to avoid the traditional route of shopping a pilot around at various networks, and ended up with the first two full episodes and scripts for the first season.

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With a cast of characters voiced by the numerous well-known comedians reached by the Duplass brothers, the series (one of the first TV shows to ever be featured at the festival) was a hit at Sundance. It was stressed that was a huge importance for the show to find a different and unique place to live in, and this was where HBO came in, allowing them all the freedom and creativity they could want – which is a lot, considering the sheer amount of improvising “Animals” relies on.

As fans might remember, Season 1 of “Animals” didn’t solely focus on the animals of New York. Instead there was an ongoing storyline in the background, as the humans of the city dealt with a political drama of their own while the animals bantered their way through New York City. With a focus on packaging each season in a fashion akin to fellow HBO bed-fellow “The Wire,” “Animals” Season 2 will be moving on into the science-fiction realm for their human counterparts with a live action episode. Centering on the villainous Dr. Labcoat, played by RuPaul, the citizens of New York will have to deal with the possibility that they may or may not be getting poisoned by a New York mega-corporation.

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With the creative freedom granted them by HBO, Matarese and Luciano were also allowed to dip into experimental storytelling beyond just allowing humans to have their own drama. Matarese was particularly excited to tease that this season would have a Killer Mike collaboration with Outkast’s Big Boi, in an episode that basically just consists of them freestyling. When improvising with any of their numerous guest stars, they emphasized that it’s generally hands-off, unless someone needs a little extra guiding to ease them into the role.

Killer Mike and Big Boi are only the tip of the iceberg of actors to come in Season 2. Fred Armisen gets to stretch his chops as a hairless cat named Alabaster in an episode reminiscent of “Goodfellas” or “The Godfather,” that also features Joe Lo Truglio and Jim Rash. We’ll also get to see January Jones play a seagull and Mindy Kaling voice a squirrel. The first episode will center on Michael Rapaport and Harmony Korine, while also featuring Emilia Clarke, Neil Casey, and Jason Alexander.

To cap it all off, Ice-T raps a recap of the first season in the credits of the premiere, which isn’t something to be missed. Check out Season 2 of “Animals” when it premieres on HBO March 17.

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