Sources & credits

Sources

BIGHT, CS Helford, the address, phone number, prices and planning figures are fiction (the number is in Ofcom's range for drama and can't ring anyone). Everything said about cables, faults, repairs and history comes from the articles below, restated in our own words.

Facts (Wikipedia, CC BY-SA)

Submarine communications cable
Cable layer
Fiber-optic cable
Optical fiber
Optical amplifier
Time-domain reflectometer
Transatlantic telegraph cable
SS Great Eastern
CS Mackay-Bennett
1929 Grand Banks earthquake
TAT-8
Porthcurno
Falmouth, Cornwall
Bight (knot)

Pictures

Lithographs by Robert Charles Dudley, 1865–66, from The Metropolitan Museum of Art, Open Access (CC0), toned blue for this site:

H.M.S. Agamemnon Laying the Atlantic Telegraph Cable in 1858
Splicing the Cable (after the First Accident) on Board the Great Eastern
Coiling the Cable in the After-tank on Board the Great Eastern

The cable, the seabed, the ship drawing and the trace are drawn in code (three.js) from the construction described in the sources.

Type, icons, code

Unispace, free for commercial use (1001fonts)
Karla by Jonny Pinhorn, SIL Open Font License
Material Symbols Light by Google, Apache-2.0, via Iconify
three.js, MIT · Lenis, MIT