The evolution from wooden ships to metal ones in the second half of the 19th century is examined. This episode opens in 1845 with a tug of war between HMS Rattler and HMS Alecto to test which was better - paddle or propeller. We reinstate HMS Warrior's place in history; in 1860, she was the largest, fastest ship in the world. The Civil War battle between USS Monitor and CSS Virginia at Hampton Roads changed naval warfare. We pinpoint the moment the USA became a global superpower when we recreate how the USS Olympia won the Battle of Manila Bay, and we show how the revolutionary British HMS Dreadnought brought ship design into the 20th century.