Decommissioned and in 1924 sold to a German company as the SS Gustavo Ipland, she was purchased and renamed by Foundation Maritime in 1930.

The book follows the tug's various captains and crews in many daring rescues during the Great Depression and World War II based out of Halifax, Nova Scotia.

The book finishes with Franklin's last voyage in January 1948 when she nearly sank while towing the Motor Ship Arosa through a hurricane.

Suffering severe damage, the thirty-year-old Franklin limped home, arriving at Halifax on February 5, 1948.

Mowat followed The Grey Seas Under with a book about Foundation Josephine entitled The Serpent's Coil.