<p>The trajectories and interaction forces of four bodies with equal masses are analytically described. The bodies follow a choreographic motion in a trisectrix limax periodic orbit without collisions. The curve is similar to a numerical curve of a folded figure of eight. The center of mass is fixed at the origin. The moment of inertia, the non-zero angular momentum as well as the kinetic and potential energies of the system are constant. The interaction forces are not Newtonian but linear attractive and repulsive forces along the lines joining the bodies. To the best of our knowledge, this is the first analytical solution to a four-body choreography in a curve other than the circle.</p>