Six ways Game of Thrones differs from the books

Brienne, the Maid of Tarth from Game of Thrones.

* This story contains spoilers

So you think you know it all because you've read the Game of Thrones novels? Well think again.

The HBO television series is beginning to differ from George R R Martin's original books.

From subtle character difference to significant scenes like last week's cyrpt incest, Martin calls the changes "the butterfly effect''. And they're going to add up to very big differences in the long run.

Here are six ways the HBO series already differs from the books.

1. Characters
In the first TV season, Ned Stark decides to go to Kings Landing while his wife Catelyn begs him to stay. In the books these roles are reversed. Cateyln is the one who is ruthless and tells Ned to go.

2. Ages
The characters in the TV series are older than they are in the books. In the novel Robb Stark and Jon Snow are 14. Sansa Stark is 11, Arya Stark is nine and Bran Stark is seven. Daenerys Targaryen is 13. HBO has bumped up the characters' ages significantly so the horror of what happens to them isn't quite as shocking.

3. Timeframe
In the books, Jamie Lannister wasn't there when Joffrey died. According to George R R Martin this goes to explain that tricky sex scene. Also in the books Cersei fears that she has lost both her son and her brother. That is when Jamie arrives back home.

"Though the time and place is wildly inappropriate and Cersei Lannister is fearful of discovery, she is as hungry for him as he is for her,'' Martin wrote on a blog.

4. Rape? Or not?
In the HBO series Cersei clearly says no before her brother Jamie has sex with her next to the dead body of King Joffrey - the product of their past incest. George R R Martin defended the scene last week because in the book the sex was not coerced.

Martin wrote: "The scene was always intended to be disturbing. But I do regret if it has disturbed people for the wrong reasons''.

In the television series Jamie had been back for weeks before Joffrey was murdered, spontaneous sex then made less sense. The scene is perhaps the biggest change caused by the butterfly effect so far.

5. Deleted characters
In season two of Game of Thrones Tyrion Lannister made his sellsord Bronn the captain of the City Watch. In the book, that never happened. The position was given to a knight named Jacelyn Bywater, who served as Tyrion's ally before dying at the Battle Of Blackwater. The HBO series combines two characters from the novels to simplify the storyline and to create a witty, more complex character that viewers will enjoy.

6. The Hound and Sansa
In the novels the relationship between the Hound and Sansa Stark was far more complex. It was such a favourite of fans that it even has its own tumblr page. But in the HBO series this relationship has been diminished by the removal of a few key elements - where the Hound tells Sansa his backstory and their interactions in the capital. Instead more time has been given to the relationship between the Hound and Arya Stark. The big question here is how this change will affect the future of the characters as the TV series moves on.

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