Technically this photo was taken several years (probably in 1986 or 1987) before Radiohead officially came to be, but it features four out of the five members, back when the group was called On a Friday.
From left to right, Thom Yorke, Phil Selway, Ed O'Brien, and Colin Greenwood. This occasion marked one of the last times that Yorke smiled for a photo. (via buzzfeed)