The Power of Six begins with the story of Number Seven, Marina (of the sea). She has found salvation (or so her Cepan claims) at an orphanage and sort of nunnery in Spain. This sequel to I Am Number Four is a lot of back and forth action and revelations between Seven and Four.
Although I found the story interesting enough with Number Four alone, Number Seven captured more of the perspective I wanted. No longer are you trapped in "Paradise" Ohio, but you're travelling across oceans and seas, finally learning the fate and story behind all of the Garde. Or at least beginning to.
And FINALLY, after so long, there was a more than PG-13 death scene. I had been previously disappointed by Henri's prolonged and overly dramatic disintegration, while the death of Hector actually had me feel for the characters.
I think that's what I love about this sequel. I feel for Six and Seven, even if I feel no attachment for Number Four. The stories of Six and Seven keep me going, knowing that it'll be worth it to continue. While their stories are either tragic or a little more depressing, they feel much more real for the circumstances that they are in.
It leaves me eager to read more of the other Gardes' stories.