Eko follows what appears to be his brother into the jungle. It turns out to be the smoke monster, which proceeds to kill Eko. Jack finds out that the reason he was captured was to operate on Ben's spinal tumor. Juliet conspires with Jack against Ben, telling him to kill Ben during surgery but to make it look like an accident. In flashbacks, Eko becomes a priest after Yemi is killed and Eko kills a few men to protect his town.
(From Wikipedia)
