Capt was the name given to the captain of an Umbrella submarine which secretly delivered a B.O.W. to a passenger vessel named the Starlight in order to allow it to retrieve it's B.O.W. Parasite which was detected on board the ship. The submarine remained docked to the ship until the parasite was returned.
The parasite was actually inside a girl named
Lucia, therefore his ultimate goal was to retrieve the girl and bring her back to Umbrella.
Unfortunately for Capt,
Barry Burton managed to make his way on board the submarine with
Lucia in tow under the pretence that he was also working for Umbrella - and after revealing his true intentions and quizzing Capt on his interest in the girl, he demanded that him and his crew work to remove the parasite from her body - which they did, but the parasite now free from it's host then attacked Capt directly and then caused a
t-Virus outbreak which turned him and the rest of his crew into Zombies.
The
Zombie captain was then killed by Barry.
His name was never revealed in the game, and was simply localised as Capt - obviously short for Captain, due to the limitations of the Game Boy Color.