Randall Einhorn is the most frequent director of the series, with 15 credited episodes.[12] The series also had several guest directors, including Lost co-creator J. J. Abrams, Buffy the Vampire Slayer creator Joss Whedon,[16][17] both of whom are fans of the series,[18][19] and filmmakers Jon Favreau, Harold Ramis, Jason Reitman, and Marc Webb.[12] Episodes have been directed by several of the actors on the show including Steve Carell, Rainn Wilson, John Krasinski, B. J. Novak, Ed Helms, Brian Baumgartner, Mindy Kaling and Paul Lieberstein.[12]