Matthews was a seaman serving aboard HMS Indefatigable. He was assigned as member of the prize crew of the Marie Galante with Hornblower in command.
In the novel Mr. Midshipman Hornblower, he was described as a tattooed and pigtailed sailor, the oldest of those assigned to the prize crew and was therefore rated a petty officer while on board.
In the television series, he was far more noticeable, a regular part of Hornblower's division in the first series, he was promoted to boatswain in the second series and served as Hornblower's touchstone in the crew. He is usually accompanied by Styles, who aboard HMS Renown was his mate.
His role was that of the knowledgeable veteran coaxing young officers along.
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