We describe a genetic algorithm to find candidates for $h^*$-vectors satisfying given properties in the space of integers vectors of finite length. We use an implementation of such algorithm to find a 52-dimensional lattice polytope having a non-unimodal $h^*$-vector which is the Cartesian product of two lattice polytopes having unimodal $h^*$-vectors. This counterexample answers negatively to a question by Ferroni and Higashitani.