  Let $U_N$ denote a Haar Unitary matrix of dimension N, and consider the field
\[ {\bf U}(z) = \log |\det(1-zU_N)| \] for z in the unit disk. Then, \[
\frac{\max_{|z|=1} {\bf U}(z) -\log N + \frac{3}{4} \log\log N} {\log\log N}
\to 0 \] in probability. This provides a verification up to second order of a
conjecture of Fyodorov, Hiary and Keating, improving on the recent first order
verification of Arguin, Belius and Bourgade.
