EXCLUSIVE: What happens when you put one of the stars with the largest cult following, Firefly‘s Nathan Fillion, on one of the top cult shows, NBC‘s Community? We’ll find out later this season when Fillion guests on the upcoming fifth season of Community. When Annie (Alison Brie) and Professor Hickey (guest star Jonathan Banks) team up to navigate Greendale’s corridors of power, they must contend with Bob Waite (Fillion), the politically savvy head custodian who’s not afraid to get his hands dirty but is smart enough to wear rubber gloves. Fillion is a fan of Community who has visited the set of the NBC show, including posting this photo with Community cast members last year with the caption, “It’s my #community dream come true!” This marks a return to comedy for Fillion who got his break on ABC’s Two Guys And A Girl before entering the Joss Whedon universe with Firefly, Buffy The Vampire Slayer and Serenity. ICM Partners-repped Fillion currently stars on the ABC crime drama Castle, now in its sixth season.