This is the only serious challenge to quantum mechanics (QM), complete with history, theory and original experiments. Here in lecture slide format you will see offprints of original famous works that reveal how the early loading theory alternative to QM was misunderstood. My repaired loading theory, the threshold model (TM), employs wave properties inspired by famous experiments. Those properties are beats, thresholds, and ratios. Previous beam-split tests are shown to be inadequate to make the QM/TM distinction. Experimental justification for a sub-quantized state is plainly revealed in many original beam-split coincidence tests with gamma-rays and alpha-rays. The sub-quantized state explains how a wave can transmit its identity and deliver a crash-landing particle-like illusion. This was demonstrated by splitting the alpha-ray (helium) in a seemingly two-for-one effect, refuting the probability method of QM. By revealing the flaw of QM and its repair, we transcend the wave-particle problem and entanglement.