TOI-431 is an orange K-type dwarf (about 0.78 solar masses, 4,850 K, 0.73 solar radii), 32.6 light-years from Earth. TOI-431 b is a 3.1-Earth-mass planet, with an orbital period of 11.8 hours, at 0.011 AU from its star, and an equilibrium temperature near 1,862 K, discovered in 2021 via transit. TOI-431 c is a 2.8-Earth-mass planet, with an orbital period of 4.8 days, at 0.052 AU from its star, and an equilibrium temperature near 867 K, discovered in 2021 via radial velocity. Mutual gravitational tugs between the planets can slowly reshape their orbits, preserving clues to the system's assembly.