within an inch of (one's) life
Almost entirely. Our neighbor is in the hospital because a burglar beat him to within an inch of his life. The sudden blaring of the alarm scared me within an inch of my life.
within an inch of your life
almost to the point of death. 1997 Marian Keyes Rachel's Holiday He kept touching his hair, which, as well as being dyed to within an inch of its life, was blowdried, flicked and rigid with spray.