Previously on Lost

Micheal came back from the other's camp, Jack & Kate found him at middle of Jungle. Micheal was weak & so he fainted.
Rose's husband tried to make a sign (S.O.S.) on sand with black rock but got management issues.
Mr. Hanry, the prisoner and everyone has a doubt that he is one of the other, is not saying anything & trying to confuse Jack, John & Sayid. John & Jack is having trust issues.
Hanry said that he didnt push the button, So John is confused. now at last Micheal killed the 2 girls in the Hatch and also hurt himself by gun to let that prisoner free from the hatch.
this is till season 2 episode 20...
Whats happens next is the biggest question? Why did Micheal do that?

lets find it out...
here the I go Episode 21st... LOST....