The underwater combustion of a propane-air mixture in an acrylic cylinder is captured on the video linked here from multiple angles. This experiment, led by Van Jones with assistance from Kariann Vander Pol and John Gilbert, is designed to provide visual data and pressure time-histories for future CFD validation studies. We have submitted this to the APS Division of Fluid Dynamics gallery of fluid motion competition this year! More information, including an extended abstract and higher resolution version of the video can be found at: http://arxiv.org/abs/1310.3523.