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We present moderate-resolution Keck spectroscopy of quasars at z= 5.82, 5.99, and 6.28, discovered by the Sloan Digital Sky Survey (SDSS). We find that the Ly α absorption in the spectra of these quasars evolves strongly with redshift. To z∼ 5.7, the Ly α absorption evolves as expected from an extrapolation from lower redshifts. However, in the highest-redshift object, SDSSp J103027. 10+ 052455.0 (z= 6.28), the average transmitted flux is 0.0038±0.0026 times that of the continuum level over 8450 Å< λ< 8710 Å (5.95< z abs< 6.16), consistent with zero flux. Thus the flux level drops by a factor of greater than 150 and is consistent with zero flux in the Ly α forest region immediately blueward of the Ly α emission line, compared with a drop by a factor of∼ 10 at z abs∼ 5.3. A similar break is seen at Ly β; because of the decreased oscillator strength of this transition, this allows us to put a considerably stronger limit, τ …