Swashbuckling movies in the best Douglas Fairbanks/Errol Flynn tradition enjoyed something of a revival in the fifties, probably because they provided the colour and spectacle which the cinema needed as a weapon in its battle with television, and Rock Hudson was one of several actors (others included Stewart Granger and Burt Lancaster) endeavouring to prove themselves the heir to Flynn.
In "Sea Devils" Hudson plays Gilliatt (we never learn his Christian name), a Guernsey fisherman-cum-smuggler during the Napoleonic wars. The plot is nothing particularly original; it is essentially a basic Cold War or World War II espionage story sent back in time to an earlier period of British history. Gilliatt agrees to transport a beautiful woman to France in return for payment. She tells him that she is a refugee from the Revolution and that she needs to return to rescue her brother, who is being held captive in a dungeon, but he later comes to suspect that she may in fact be a spy for the French. Gilliatt may cheerfully disregard British law, at least as regards the evasion of import duties, but remains a patriot at heart, so is horrified that he may have played a part in assisting the enemy. Or is the lady in fact a double agent who has been working for the British all along? A sub-plot involves Gilliatt's rivalry with another smuggler, the villainous Rantaine, who has no qualms about helping the French provided he is paid enough.
Hudson's leading lady here is Yvonne De Carlo who (like a number of his leading ladies from the fifties, Jennifer Jones in "A Farewell to Arms" being another example) was slightly older than him. Although the age difference in this case was not great (Rock was 28 in 1953, Yvonne 31), this perhaps made him unusual in a decade when Hollywood's leading male stars were often cast against much younger women. I certainly can't agree with the reviewer who found Yvonne too old for the part; in the early fifties she was one of Hollywood's loveliest female stars.
"Sea Devils" is reasonably entertaining, but it has no great action set- pieces and it cannot compare to the really great swashbucklers like the Errol Flynn "Adventures of Robin Hood" or "The Sea Hawk". It does, however, remain watchable today, if only for the charisma of its two leads. 6/10
Some goofs. Although the film is set in 1800, Napoleon is referred to as "Emperor" of France. He did not become Emperor until 1804; in 1800 his title would have been First Consul. The French name "Lethierry" is consistently mispronounced as "Letheery".