Surface ruptures of past earthquakes and exhumed fault surfaces reveal that faults are often nonplanar at a large range of length scales. This multi-scale complex geometry is suggested to affect rupture characteristics, such as the rupture velocity, slip rate, and size, as well as the seismic signal. Yet, constrained experimental evidence of these effects is lacking. Here, we present the first direct measurements of the interaction of experimental ruptures with nonplanar geometry. We use ultrahigh-speed photography and image correlation to resolve the full-field dynamics that evolve as shear frictional ruptures propagate through different geometries, from single restraining or releasing bends to rough with multi-scale asperities. We produce geometries with varying degrees of roughness, controlling the height-to-width ratios and minimum wavelength of the asperities. We observe how nonplanar geometries complicate the ruptures, transitioning them from sub-Rayleigh to supershear velocities and pulse-like to crack-like style, and how they excite additional seismic waves. These results show that fault geometry is a key parameter controlling earthquake dynamics, with implications for earthquake modeling, interpreting seismic signals, and earthquake hazard assessment.