Season 4 - Episode Guide

A deadly design flaw results in a horrifying rush hour bridge collapse that tragically leaves 13 dead in Minneapolis; using the latest science, experts investigate to reveal what went so catastrophically wrong on one of Minnesota's busiest crossings.

A massive sinkhole swallows millions of dollars of legendary automobiles at the National Corvette Museum in Kentucky; expert geologists investigate and reveal how an enormous cave system could remain undetected and poised for catastrophic destruction.

A devastating rail disaster outside the small town of Casselton, North Dakota, results in cargo erupting in massive explosions; experts use the latest science to investigate and uncover an engineering flaw poised for catastrophic failure. 

A series of violent explosions rip through a major Texas oil refinery, causing a fatal disaster and devastation on a terrifying scale; experts use the latest science to investigate and uncover what triggered a catastrophic malfunction. 

Tragedy strikes a bustling Canadian shopping mall when a parking garage suddenly collapses resulting in a fatal disaster; expert engineers use the latest technology to investigate and uncover a deadly design flaw that could have been prevented.

Construction turns catastrophic in New Orleans when the side of a hotel complex collapses on a busy street below; expert engineers investigate to uncover the reason behind this sudden and fatal disaster. 

A deadly tragedy on a freeway in Oklahoma sends one of the state's busiest bridges collapsing into the Arkansas river below; expert engineers investigate how a tugboat striking a reinforced concrete pier could cause such a catastrophic disaster.

When an indoor hotel walkway collapses in Kansas City, Mo., it becomes the most deadly engineering disaster in U.S. history; experts investigate and uncover evidence of a catastrophic design change in the support system construction.

A shipping catastrophe occurs when a massive container vessel, the Ever Given, runs aground and completely blocks the Suez Canal, one of the most vital trade routes on the planet; experts investigate and uncover critical wind conditions and potential navigational errors.

A vital hillside highway in Pennsylvania is destroyed in just minutes after a catastrophic landslide rocks a community; engineers investigate and uncover undetected geological issues with an increased and unstable traffic load.