This rescue proves somewhat difficult, as Joanna is being kept well guarded in a house by the sea. Dick's first attempt, involving the outlaws and a stolen boat, is a fiasco, ending in disaster. After this, Sir Daniel moves Joanna to his main residence, and Dick manages to sneak in to see her disguised as a friar. He then meets up with Joanna's actual guardian, Lord Foxham, who is also attempting to rescue her, and who promises to give Dick her hand in marriage if he can get her back. Unfortunately, Lord Foxham is seriously wounded in a second unsuccessful rescue attempt, and he asks Dick to keep his rendezvous with the Duke of Gloucester for him.
To sum up, The Black Arrow is a much more interesting book than its movie would lead you to believe, and I would recommend reading the former and skipping the latter.