Many readers will likely know the story of "Galloping Gertie," the Tacoma Narrows Bridge that, on November 7, 1940, under the sway of a powerful wind, began to make powerful undulating motions - until it collapsed into the Puget Sound hundreds of feet below. But what really happened? For decades physicists have used the doomed bridge as a dramatic object lesson in resonance, the tendency of a system to oscillate at large amplitudes at certain frequencies. New research, however, has challenged that assumption. Aside from the erudite explanations in this article, written by Alex Pasternack and published on Motherboard, readers will find stunning film of Galloping Gertie, as it shifted and shaked, as well as period photographs, and several YouTube videos with alternate explanations for the bridge's failure. Anyone who loves a good engineering mystery will find much to appreciate in this well written article.