A New York City skyscraper that could topple at any moment is examined.

A skyscraper sinking into the earth, the world's strongest wall in crisis, and a deadly bridge are engineering catastrophes in need of repair, and experts use cutting-edge technology to reveal what went wrong and if they can be fixed.

A railroad bridge on the edge of disaster, a nightmare in a fairy-tale town, and a massive cathedral in calamity are engineering catastrophes in need of repair, and experts use cutting-edge technology to reveal if they can be fixed.

A skyscraper causing hellish heat in downtown Dallas, a swarm of sinkholes, and a landmark with a fatal secret are engineering catastrophes in need of repair, and experts use cutting-edge technology to reveal what went wrong and if they can be fixed.

A town finds itself close to annihilation when a dam threatens to burst.

A fire in an American town burning since 1962, a massive flood that threatens Chicago's iconic skyscrapers, and a town swallowed by the sea are engineering disasters in need of repair, and experts reveal what went wrong and if they can be fixed.

An abandoned Vegas-style getaway with a deadly secret, a ghost town sinking into the earth, and a passenger train on course for disaster are engineering catastrophes in need of repair and experts use cutting-edge technology to reveal what went wrong.

A skyscraper rained deadly bolts on the streets below, a highway on the brink of collapse, and a catastrophic landslide are engineering crises in need of repair. Experts use the latest science to reveal what went wrong and if disaster can be averted.

When catastrophe strikes Skylab, life on earth is threatened by a space station cratering toward earth, and NASA experts use cutting-edge technology to reveal what went wrong and if disaster can be averted.

A detonated building mysteriously refuses to fall, an American ghost town with a deadly legacy, and wind turbines on the brink of disaster are engineering disasters in need of repair, and experts reveal what went wrong and if they can be fixed.

Engineers race for solutions to bring down buildings that refuse to fall.

Powerful explosives fail to bring down the Pontiac Silverdome in Michigan.

When an oil rig in Louisiana drills into something unexpected, a cataclysmic event is unleashed, causing a lake to suddenly disappear; experts use the latest science to investigate what went wrong and how it can be fixed.

When a brand-new bridge suddenly collapses in Miami, several die in a horrifying calamity; experts use the latest science to investigate what went wrong and how an innovative bridge-building technique could be to blame.

When a dam breaks during routine maintenance, engineers fear a catastrophic flood; experts use the latest science to investigate what went wrong and how a simple miscalculation could be to blame.

What would happen if we got a message from space? How would we react? Scientists and sci-fi writers, with cooperation from SETI and Carl Sagan's son, Nick, unravel the impact of this world changing event, forming an intriguing hypothetical scenario