Walter is one of several assassins trying to kill McGarrett and Nicole Wylie at a temple supposedly in the Philippines, which is actually the Byodo-In Temple located on Oahu. Walter is seen shooting, then leaps over a railing and runs through some bushes. After this, it looks like Walter is shot and changes into stuntman Beau Van Den Ecker, who falls into a pond. But then a cop tells Walter to put his hands up, suggesting that he was never shot, or he is a totally different character. See my review of this episode for a breakdown of this sequence in the "More Trivia" section.