 Andrew Santella wrote for "The New York Times", "Powers's latest genre-blending thriller (call it an occult/fantasy/espionage/existential adventure with elements of paranoid rant) concerns shadowy groups of international intriguers racing to locate a lost discovery of Albert Einstein's that could quite literally change history.... Frank Marrity, an English professor, and his 12-year-old daughter, Daphne, stumble on Einstein's secret and scramble to figure out what it means and how to keep it and themselves out of the hands of the mysterious groups — Mossad?the N.S.A.