He took up residence at St Mary Hall, Oxford University, leaving after two terms to resume his former life. His gift of improvising songs charmed the Prince Regent into a declaration that something must be done for Hook, who was appointed accountant-general and treasurer of Mauritius with a salary of £2,000 a year. He was the life and soul of the island from his arrival in October 1813, but a serious deficiency having been discovered in the treasury accounts in 1817, he was arrested and brought to England on a criminal charge. A sum of about £12,000 had been abstracted by a deputy official, and Hook was held responsible.