Particle physics is occasionally likened to trying to understand how a Swiss watch works by smashing it to pieces, using an increasingly energetic series of hammers, and studying the bits that fly out. However, this experiment at the Institut Laue-Langevin in Grenoble, France, run by research groups at the University of Sussex, the Rutherford Appleton Laboratory, the University of Kure, and Oxford University, is adopting a gentler approach in its investigations of the fundamental properties of matter. Information is teased out of bunches of very low energy ('ultracold') neutrons by gently perturbing their spins with small electric and magnetic fields, and then observing their responses. Such measurements are incredibly precise, and offer a very different means of testing our standard theories of particles and forces than by colliding particles at very high energies.