Follow the epic operation to secure, raise, and salvage the Costa Concordia cruise ship, which ran aground and tragically capsized off the coast of Italy on January 13, 2012, killing 32 people. The massive wreck—with a 160-foot-long hole in its hull—stretches the length of three football fields, weighs 45,000 tons, and was half submerged on the site of a protected reef. Moving it from its precarious perch on the edge of an underwater cliff turned into a technical and logistical challenge of staggering proportions. Join NOVA as we follow a team of more than 500 divers and engineers working around the clock as they attempt the biggest ship recovery project in history.

One of the ancient world's most iconic buildings, the Colosseum is a monument to Roman imperial power and cruelty. Its graceful lines and harmonious proportions concealed a highly efficient design and advanced construction methods that made hundreds of arches out of 100,000 tons of stone. In its elliptical arena, tens of thousands of gladiators, slaves, prisoners, and wild animals met their deaths. Ancient texts report lions and elephants emerging from beneath the floor as if by magic to ravage gladiators and people condemned to death. Then, just as quickly, the Colosseum could be flooded with so much water that ships could engage in sea battles to the delight of the crowd. Now, archaeologists and engineers are teaming up to recreate a 25-foot lifting machine and trap door system capable of releasing a wolf into the Colosseum's arena for the first time in 1,500 years. Do they have what it takes to replicate the innovation and ingenuity of the Romans?