X-Machines takes a look at the largest and most technologically advanced machines from around the world. Visually stunning, the series shows how machines work and documents both the ingenuity of the project management teams and the skills of those who operate them. Witness the world's highest-flying lift helicopter on a mission to save a historic gold mining town high in the Colorado Mountains in America. Another episode features Nemo, a futuristic submersible exploration vehicle that can dive to depths of over 900 metres, watch as it checks Lake Tahoe's fault line in response to the growing concerns of a potential tsuami wave. Fast paced and dramatic, this series takes engineering to a fascinating new level.