From Brickipedia, the LEGO Wiki
All the Adventurers have names related to weather, a precedent kept in the contemporary Pharaoh's Quest theme.
- Johnny Thunder: The leading man in the LEGO Adventurers line. He is Australian and is a daring, compassionate archaeologist. He sports a khaki shirt with a red bandanna, has black legs, and a brown bush hat.
- Dr. Charles Lightning (aka Dr. Kilroy): One of Johnny Thunder's companions on his epic adventures. He is a professor and is like a father figure to Johnny. He sports a pith helmet, a white shirt with a red bow-tie, and green legs.
- Gail Storm (aka Pippin Reed): The female companion of Johnny Thunder who is a budding journalist for the 'WORLD' Magazine, recording all of his adventures. She sports a green, brown, or tan jacket, red legs or tan legs, and either a pith helmet or pilot helmet.
- Harry Cane (aka Hurrykain): One of Johnny Thunder's best friends, who is an experienced pilot. He wears a pilot helmet with a leather jacket and black legs. His name is a play-on-words of 'Hurricane', thus relating to weather like his fellow adventurers.
- Baron Von Barron (aka Sam Sinister, Sam Sanister, Lord Sinister, Lord Sam Sinister, Mr. Hates, Evil Eye): The main villain in the Adventurers line, he seeks to take things he considers valuable, including dinosaurs. He has a scarred face and sports a monocle, khaki shirt with holster, grey legs, epaulets, and either a pith helmet, top hat, or pilot helmet. His left hand is a hook. He is one of the most-wanted men in the LEGO world. In explanation of his many different names, it is said that he is constantly changing his name to avoid capture by the authorities, but Sam Sanister is probably his real name, and since "Sanister" sounds like "Sinister", that is probably where he got his current title.
- Slyboots: Sidekick or partner to Baron von Barron. One of the main villains, he dresses entirely in black and is a representation of the archetypal "villain". He was originally called Sam Sinister, but when the Baron took the name in the later years, he was renamed Slyboots. This confusing name change has since been acknowledged, and joked about, by the LEGO Group itself.
- Pharaoh Hotep: An undead Pharaoh who guards the magical Re-Gou Ruby.