  We solve, using localization, for the large-N master field of N=2*
super-Yang-Mills theory. From that we calculate expectation values of large
Wilson loops and the free energy on the four-sphere. At weak coupling, these
observables only receive non-perturbative contributions. The analytic solution
holds for a finite range of the 't Hooft coupling and terminates at the point
of a large-N phase transition. We find evidence that as the coupling is further
increased the theory undergoes an infinite sequence of similar transitions that
accumulate at infinity.
