When Henry was first built, he was a failure. He was built using rejected plans for Sir Nigel Gresley's A1, they were stolen by a rival company. The result, was a mix of a GNR A1 Pacific and a GNR C1 Atlantic, with a 4-6-2 wheel arrangement. His firebox was undersized, this made him steam badly. He was given Welsh coal, which seemed to be the cure for Henry's bad steaming. But one night, Henry had a accident with the train called 'The Flying Kipper'. He was sent to Crewe Works and came back with a new shape, a LMS Stanier "Black Five" 5MT. He is now one of the strongest engines on the NWR and since 1967 he has taken heavy goods trains to London and Derbyshire.
Henry is a friendly engine and the engines enjoy to work with him, however this does not mean he is always friendly. He tries to impress Gordon and for the most of the time, he is always agreeing with what Gordon says even if it makes him sound rude, arrogant and stupid.