Traditional wisdom suggests that good things come in threes. From the Bronte sisters to Destiny's Child, there's something undeniably magical about the number three. 


Sometimes though, three is just the beginning. Case in point: E.L. James’s new book, Grey, which is not so much a continuation, but a deeper exploration of the world set up by the original trilogy. Told from Christian Grey’s point of view, Grey is proof positive that good things don’t always come in threes.



Some authors keep writing past the three book mark because they feel they have more to explore in their created world. For others like James, however, the continuation of a series is largely due to untapped reader demand. Whatever the reason, these series additions are often beloved and much talked about.


To celebrate James’s much anticipated new novel, we thought we’d look at a handful of other trilogies that carried on long after their third instalments.



The Divergent Series by Veronica Roth

After the runaway success of Roth’s Divergent trilogy, Roth decided to treat her fans to a little extra, with Four: A Divergent Collection (2014). Serving as prequel to the trilogy, the book is a collection of five short stories, told from Tobias Eaton's (AKA Four) perspective.



The Millennium series by Stieg Larsson

Sometimes a trilogy can outlast its author with a new writer continuing its legacy. The Girl in the Spider’s Web, the fourth instalment in Stieg Larsson’s Millennium series, will be published on Sept. 1, marking the continuation of one of the most beloved and successful literary franchises of the 21st century. Carrying the torch this time around will be David Lagercrantz, who was handpicked by both the publisher and the estate of Stieg Larsson, who died in 2004 before the publication and worldwide success of his trilogy of crime novels.


The Lord of the Rings by J.R.R Tolkien

It’s often debated whether The Hobbit should be properly considered part of LotR or a standalone work. These debates are often followed by further arguments over whether or not Thranduil's dad was the elf responsible for abandoning Dol Guldur, before Sauron moved in or if Durin's Bane, the Balrog who took the epic fall with Gandalf in The Fellowship, actually had wings. We have no comment.





The Song of Ice and Fire by George R R Martin

Believe it or not, Game of Thrones was almost a whole lot shorter. When GRRM originally began writing the series, he had a trilogy in mind. Thank the Gods (both old and new) that at some point he changed his mind.


The Crossfire series by Silvia Day

Originally billed as a trilogy, Crossfire fans were treated to trilogy-busting fourth book in late 2014 with Captivated By You. And that’s not all: the series is now in the early stages of development for a television adaptation.


The Sleeping Beauty Series by Anne Rice

Written under the pen name of A.N. Roquelaure, Anne Rice’s sensual re-telling of the Sleepy Beauty story became a cult hit (and subject of much controversy for its depiction of both maledom and femdom scenarios) when the trilogy was originally published in the ‘80s. In April of 2015, Rice released Beauty’s Kingdom pushing the series to four.


The Hitchhiker's Guide to the Galaxy by Douglas Adams

Never one to miss out on an opportunity for self-deprecation, Douglas Adams mocked his best-selling series for being "a trilogy in five parts." When Eoin Colfer penned a sixth instalment in 2009, it earned the distinct honour of being the first ever six part trilogy.


Cormoran Strike series by Robert Galbraith

JK Rowling, writing as Robert Galbraith, is set to release her third instalment in the Cormoran Strike series in 2015. No word yet if she's going to call it a trilogy or a series -- and either way, there's no telling how many more entries there'll be, but we hope there are plenty more stories to come.


More and more, we’re seeing that stories need not be constrained to neat little three part packages. Indeed, this is an especially rich season for lovers of literary trios (and beyond). Which one are you most looking forward to?