Captain Antilles was the captain of the Tantive IV, to whom R2-D2 and C-3PO were given by Obi-Wan Kenobi and Bail Organa shortly after the Clone Wars. After the fall of the Old Republic, Captain Antilles was tasked with transporting Princess Leia Organa and the stolen plans of the Death Star safely to Alderaan. When the Tantive IV was captured by agents of the Galactic Empire, Antilles perished at the hands of Darth Vader when he denied that his ship carried the Death Star plans.
Although it is clearly Captain Antilles who dies at the hands of Darth Vader in the film version of A New Hope, the novelization names the man Vader kills "Captain Colton." For some time fans assumed that "Colton" was actually Captain Antilles' first name, but Revenge of the Sith reveals that Colton is an entirely different character and is Antilles' second-in-command. Therefore, although Colton's fate in the films is unknown, absent as he is from A New Hope, in the novel he is killed by Vader, making it Antilles whose fate is unknown.