This is a hypothetical animation of what most likely occurred resulting in the Deepwater Horizon offshore disaster. The causes of the Deepwater Horizon drilling disaster at the BP Mississippi Canyon 252 #1-01 were a series of linked events. It is possible that other factors could have lead to the same disastrous result, but based on the data and testimony offered to date, the explanation for the blow out rests with the decision to run a long string of production casing linking the bottom of the well to the top. This became the pathway for reservoir fluids to the surface. The second contributing factor was the creation of a path through the cement that would have been the only barrier for gas movement in the annulus. The third was the failure of the well head seals when sea water replaced the drilling mud in the marine riser. Once the gas escaped into the marine riser the crew had little time and perhaps few tools to block the flow of this gas to the surface. Lastly, once the gas reached the surface and was ignited the destruction of the drill floor and possibly the upper control sections to the BOPS, the BOPS likely could not be activated by controls on the rig. The "dead man switch" failed to activate because the battery in the subsea control pod was dead. The ROVS used later also failed to activate the BOPS possibly due to the failure of the hydraulic pressure systems, improper rams in the BOPS, and/or the drill pipe was lodged in the BOPS at an unexpected angle or position after it was dropped from the surface.