Hall returned to the ship from an exploratory sledging journey, and promptly fell ill. Before he died, he accused members of the crew—the expedition's lead scientist, Emil Bessels, in particular—of having poisoned him.

Hall went on his first expedition by gaining passage on the George Henry, a whaler commanded by Captain Sidney O. Budington out of New Bedford.

On his return to New York, Hall arranged for the Harper Brothers to publish his account of the expedition: Arctic Researches and Life Among the Esquimaux.

Over the course of 1863, Hall planned a second expedition to seek more clues on the fate of Franklin, including efforts to find any of the rumoured survivors or their written records.

The first attempt, using the 95-ton schooner, USRC Active, was abandoned, probably owing to lack of finances caused by the American Civil War and a troubled relationship with his intended second-in-command, William Parker Snow.

Hall eventually came to believe that the stories of survivors were unreliable, either by the Inuit or his own readiness to give them overly optimistic interpretations.

Other whalers in the party claimed the attack occurred because Hall was angry that Coleman was interviewing local Inuit without his permission.

The party of 25 also included Hall's old friend Budington as sailing master, George Tyson as navigator, and Emil Bessels as physician and chief of scientific staff.

That fall, upon returning to the ship from a sledging expedition with an Inuit guide to a fjord which he named Newman Bay, Hall suddenly fell ill after drinking a cup of coffee.

After wintering ashore, the crew sailed south in two boats and were rescued by a whaler, returning home via Scotland.

A group, including Tyson, became separated as the pack broke up violently and threatened to crush the ship in the fall of 1872.

Tests on tissue samples of bone, fingernails and hair showed that Hall died of poisoning from large doses of arsenic in the last two weeks of his life.