'The Duel' ( a.k.a. 'The Even Chance') is the first movie in the Hornblower series, and it introduces us to Horatio Hornblower as well as several other characters who will figure prominently in this film, and in the series as a whole. It also sets the scene: the English navy at the time of the French Revolution and the Napoleonic Wars, when Britannia really did "rule the waves."
When we first meet Horatio, he seems to have many disadvantages which would preclude a successful naval career. At 17 years of age, he is considered old to be starting in the service, where many go to sea at twelve. He is the rawest of beginners, and suffers from sea sickness, which will afflict him periodically throughout his life. As well, we learn in a letter from his father to Captain Keene that Horatio is a "solitary boy." In the cramped, crowded environs of a naval vessel, there is no place for privacy or solitude.
On the other hand, in the small world of the ship, through common experiences and shared dangers and difficulties, Horatio forms a few solid and lasting friendships much faster than someone of his nature probably would under different circumstances. As well, what he lacks in experience, Hornblower makes up for in intelligence and natural ability. Early on in this film, we see him excelling in his navigational training, surpassing those who have been at it much longer.
It is this competence and skill which first incites the ire of Simpson, as these are qualities that he himself lacks. He also lacks any semblance of a conscience, appearing to be a sociopath. Simpson cares nothing for his duty to his country or crew; his only concerns are his own twisted ambitions. As well, he responds to personal failure by trying to punish others for their success. He's pretty much the antithesis of Hornblower, who constantly strives to better himself, and has a highly developed sense of duty and honour, as well as an innate kindness of character.
It is when Horatio is transferred to the Indefatigable, under the command of Captain Pellew that he begins to take strides toward becoming the officer- and the man- he wishes to be. Pellew is gruff and tough, and he has no reason to think well of Horatio, but as he says, "I judge a man by what I see him do, not what others tell me he has done." He gives Hornblower the opportunity to prove himself, and Horatio rises to the challenge. It is from Pellew that Hornblower begins to understand what the demands and responsibilities of military command are. For example, in their initial interview, Pellew states, in regard to the duel, that it wouldn't have occurred if they'd been properly led. Horatio attempts to defend Captain Keene, saying that what happened was beyond his control. Pellew snaps back that, on a ship, nothing is beyond the captain's control. This is part of the burden of command: ultimately, for good or ill, responsibility lies with the leadership.
It would be impossible to discuss the Hornblower series without mentioning the men of Horatio's - formerly Simpson's- division. There is very much an 'Upstairs, Downstairs' element in the story- there's the officer class, and then there are the ordinary seamen like Styles, Matthews, etc. There's an old saying that "no man is a hero to his valet," and this holds true for sailors as well. A good deal of amusement is derived from their observations and salty comments about the doings of their "betters." But there is a serious element to this as well. Life on a naval ship was dangerous at the best of times, and especially during war, when the seamen were expected to not only sail the ship, but fight in its battles as well. Poor or reckless leadership could mean the difference not only between success or failure, but between life and death as well. The men had a vested interest in having able commanders. This is why, though originally insubordinate to Hornblower, they quickly recognize his strength of character and ability, and become completely loyal to him.
The Duel is a great introduction to the Hornblower series. It not only allows us to get to know main characters- especially Horatio- with all their faults and virtues, but presents us with various themes and issues which will recur throughout the films: concepts of duty and honour, moral and physical courage, personal responsibility, and self-sacrifice. Above all, it is the story of a boy coming of age in a time of war, struggling to prove his worth to his captain and his men, and perhaps most of all, to himself.