_At the beginning: Sakura was showed to have open a clinic for children, then she and Ino asked Kakashi for permission to go to Suna, for establishing another similar clinic there.
_At the same time, Sai was sent to invest a case
where a Lord got attacked in the hot spring.
_When the two girls got to Suna, they are told by Gaara that there is a mysterious person that was assumed to be Sasuke (Because that person has a similar appearance and even charka to Sasuke), this person approached the terrorist groups to buy weapon, intend to attack Konoha again.