While quantum mechanics has been able to answer many practical questions about the structure and bonding of atoms, molecules, nuclei, and even subatomic particles, it still does not adequately yield its own ultimate meaning. The ability of an electron to be in more than one place at once, to appear on both sides of a node, and to have no defined boundary are only the "down payments" for the mysteries of quantum mechanics, about which even its developers were conflicted. I was fortunate to have heard a David Mermin lecture based on his famous Physics Today (1985 38(4) 38) article, "Is the Moon There When Nobody Looks?", an understandable introduction to the disturbing consequences of what is called "entanglement" that is still well worth reading. The first part of Gilder's description of modern quantum mechanics does not break much new ground, but this reader tuned in when she began to describe David Bohm and his "hidden variables" attempts to find a deterministic interpretation. She builds her history through real correspondence and imagined but plausible conversations between the likes of J. M. Jauch, John Bell and interviews with Nicolas Gisin and Anton Zeilinger. She may have filled some gaps with conversations that never occurred, but through that, she has made clear the disturbing truth about the meaning of quantum mechanics.