Unless you've made it a point to re-watch Batman Begins and The Dark Knight in the past few weeks, there are some essential characters you'll need to brush up on before seeing The Dark Knight Rises. It's pretty clear now that director Christopher Nolan and his screenwriting partners have always intended this trilogy to be one long interrelated story, and there are characters, themes, and even lines of dialogue (Selina Kyle's "There's a storm coming" is preceded by Batman's line to Sergeant Gordon — "Storm's coming" — in Batman Begins) that are repeated throughout all three films.
1. The League of Shadows
After his failed attempt to avenge the death of his parents in Batman Begins, Bruce Wayne goes on a walkabout and ends up in the mountains of Asia in the company of the League of Shadows. The group is a secret organization of ninjalike assassins who take as their mission the restoration of global balance through the destruction of corrupt civilizations, like Gotham City. After training with the group in the areas of martial arts, deception, and theatricality, Wayne tries to bring down the organization. Wayne discovers that the League once tried to undermine his city through financial terrorism, which led to a depression combated by his father.
2. Ra's al Ghul:
The head of the League of Shadows, also known as Henri Ducard (Liam Neeson). He trains Bruce Wayne and then later tries to kill him and destroy Gotham through the use of a Wayne Enterprises experimental device that would shoot a nerve toxin into the atmosphere, driving the populace mad. (It's worth remembering the developer of the toxin is Dr. Jonathan Crane, a.k.a. The Scarecrow, who also appears briefly in The Dark Knight.) He fails and is killed by Batman.
3. Harvey "Two Face" Dent:
Gotham City's District Attorney, Dent is hard on organized crime and is considered the city's "white knight" (as opposed to Batman, its dark knight). His face is severely maimed (essentially divided in two) following an explosion at the hands of the Joker. Towards the end of The Dark Knight, he goes insane, murders several cops and almost kills Commissioner Gordon's son before being stopped by Batman. Yet, in order to keep his memory alive as a hallowed crime fighter in the minds of Gotham's citizens, Batman takes the blame and goes on the lam — which is how the second film ends.
4. Rachel Dawes:
A Gotham City assistant district attorney and childhood friend of Bruce Wayne. Portrayed by Katie Holmes in Batman Begins and Maggie Gyllenhaal in The Dark Knight, Rachel knows the identity of Batman and is torn between the love of Dent and Wayne. After the Joker puts Dawes and Dent in separate explosives-filled buildings and tricks Batman into saving Dent when he thinks he is saving Rachel, Wayne mourns for the loss of his love. Little does he know that she actually chose Dent, a fact relayed in a letter that Wayne's butler Alfred chooses to destroy rather than further hurt his boss.