Face the challenges of constructing London's colossal new commuter railway.
EPISODE 1
Super Tunnel
A massive boring machine carves a 42-kilometre shaft under London.
EPISODE 2
Drilling down on a fresh passage under the Thames and a rebuilt Victorian tunnel.
EPISODE 3
Wrestling with a complex underwater assembly and unearthing London's gruesome past.
EPISODE 4
A look at battle fault lines and a Victorian station update; also, a special guest.
EPISODE 5
A look at Paddington's glass canopy and a father-son duo finishing 66 trains.
EPISODE 6
The Elizabeth line's safety is put to the test; also, a look inside a vast commuter hub.