Until 2012, all of my books were stand-alone, which meant that readers did not need to read any particular book first. There were a couple that had the same characters, such as the true story of Mary Neely in River Passage and Songbirds are Free. But if you read them in reverse order, you would still understand what was happening with each character.
Black Swamp Mysteries series was launched, due to the popularity of Exit 22, which introduced Brenda Carnegie and Christopher Sandige.
Vicki's Key introduced two new characters, Vicki Boyd and Dylan Maguire, so the reader didn't need to read Exit 22 in order to understand what was happening.
Secrets of a Dangerous Woman, all four characters came together - and what transpires in that book keeps these characters together for the rest of the series, either through blood or circumstance.
Dylan's Song, which was released in early 2013, picks up where Secrets leaves off... And if you didn't read the first few books in the series, you'd find yourself kind of... lost.
Copper, about New York during the era of the Civil War. Turns out it has quite a few Irish hunks on it - actors who could easily play Dylan Maguire (Black Swamp Mysteries series) or Ryan O'Clery (The Tempest Murders).
But I found myself completely lost when I watched the first show of this season. Turns out, I didn't understand the relationship between the men and women and children... And I didn't understand what was going on.
So I had to go back to Season I to watch those first critical episodes that explains who everyone is, where they came from, who they're related to, and so on.
Has this happened to you, either in a book or with a television series?