It's difficult to watch 1940's The Sea Hawk without thinking of 1938's The Adventures of Robin Hood. The films share several principal cast members (Errol Flynn, Claude Rains, Donald Crisp, Alan Hale) as well as a director, Michael Curtiz. Though while Curtiz was the final credited director of Robin Hood, that earlier film actually changed hands several times. The Sea Hawk, while inferior to Robin Hood, feels more like a Curtiz movie all the way through and is a solid swashbuckler with beautiful production design.
Curtiz and Flynn had made another pirate film together in 1935, Captain Blood. The Sea Hawk is a great deal more light hearted and its plot much closer to that of the Robin Hood film. Flynn plays privateer Captain Geoffrey Thorpe, secretly employed by Queen Elizabeth I. Like Robin Hood, Thorpe robs England's enemies in service to her true liege.
Loosely based on some of the exploits of Sir Francis Drake (rather than on the Raphael Sabitini novel from which the movie gets its name), the movie is largely concerned with intrigues leading up to the Spanish Armada's move against England. Claude Rains, rather than playing the usurper Prince John, plays the Spanish Ambassador who manipulates the English court. Rains plays this fellow with more restraint than he played John, coming across as a subtle puppeteer. Instead of Basil Rathbone, his chief cohort is Henry Daniell as Lord Wolfingham and they scheme and talk down their noses at each other.
I love Daniell but he's not as well served here as Rathbone. He and Flynn have a sword fight at the end that superficially resembles the one between Flynn and Rathbone with slashed candles and giant shadows but lacks all the intensity and precision that make that earlier duel so remarkable.
In fact, the swordplay in this film is consistently disappointing, generally looking like the two combatants are waving feather dusters at each other.
Brenda Marshall replaces Olivia de Havilland as Flynn's love interest. She's beautiful, but not half the performer de Havilland is. She has a similar familial relationship with Claude Rains' character to the one Maid Marian had with Prince John though while John seemed to regard his brother's ward as nothing more than a piece of his retinue, the Spanish Ambassador seems to feel genuine pain when he learns of Marshall's love for Thorpe and her sympathies for England.
Unlike Robin Hood, this film was mostly shot in black and white, except for the sequence which takes place in Central America, which is sepia. Curtiz makes use of both formats excellently, combined with the intricate detail on the ships and costumes to give the visuals a genuine antique feel.
Flynn plays Thorpe as a far less jovial character than Robin Hood, far more sensitive to proprieties despite being in the business of plunder. Rather than the extended prank of his feast with Sir Guy and the Sheriff of Nottingham, the dinner he lays out for his captured foes aboard his own vessel feels more like a courtesy he's genuinely extending to honour his defeated adversaries. In comparison to Robin Hood, this performance is sort of charming, but I think I'd generally prefer the man who speaks treason "fluently".