I will present a preliminary result on the third-order correction in 1/N expansion to the four-point correlator of the stress tensor multiplet in N=4 super Yang—Mills theory at large ’t Hooft coupling, which corresponds to the two-loop scattering of four gravitons in the dual AdS5×S5 supergravity. This is obtained by bootstrapping an educated ansatz based on intuitions from the hidden 10-dimensionthe conformal symmetry, which I will describe in detail.