Buck has written for several television series including Six Feet Under, Rome, Showtime's Dexter, Everybody Loves Raymond, Coach, Inhumans, The Oblongs and Iron Fist.

He remained a co-executive producer for the fifth and final season in 2005 and contributed two more episodes – "Dancing for Me" and "Singing For Our Lives".

He wrote two episodes for the series ("These Being the Words of Marcus Tullius Cicero" and "Death Mask") before it was canceled.

[6] In December 2015, Buck was hired to serve as showrunner and executive producer for the Marvel and Netflix television series Iron Fist.

[7] In December 2016, Buck was named showrunner and executive producer for the Marvel, IMAX Corporation, and ABC television series Inhumans.