Story arcs on television (and also on radio) have existed for decades (one notable (albeit, unusual) example, from the so-called "Golden Age of Radio", being the 1946 NBC Radio Summer-run docudrama serial, "The Fifth Horseman", which (in part) featured a four-episode arc regarding a hypothetical chain of events (spanning nearly two full "future" decades) surrounding a fictitious nuclear holocaust), and are common in many countries where multi-episode storylines are the norm (an example being the UK's "Doctor Who"), as well as most anime series.