Mayberry R.F.D. is an American television series produced as a spin-off and direct continuation of The Andy Griffith Show. When star Andy Griffith decided to leave his series, most of the supporting characters returned for the new program, which ran for three seasons on the CBS Television Network from 1968–1971. During the final season of The Andy Griffith Show, widower farmer Sam Jones and his young son Mike are introduced and gradually become the show's focus. Sheriff Andy Taylor takes a backseat in the storylines, establishing the sequel series. The show's first episode, "Andy and Helen's Wedding", had the highest ratings in recorded television history. Sheriff Taylor and newlywed wife Helen make guest appearances on RFD until late 1969, and then relocate with Opie. Mayberry R.F.D. was popular throughout its entire run, but was canceled after its third season in CBS's infamous "rural purge" of 1971. R.F.D. stands for "Rural Free Delivery", a quaint postal depiction of the rural Mayberry community.