Charlie Wallace is an Ekaterina agent trying to protect one of the 39 Clues.
In 1985 after Grace Cahills plane carrying the Clue Phosphorus crashed in Loch Ness, the Ekats couldn't move it due to attracting Lucian attention, so they sent Charlie a letter instructing to protect the Clue using the Loch Ness Monster myth. Charlie created the Nessie Shack promoting that the Monster existed, and created the Wee Nessie Submarine which he piloted around. When Paul Addison came questioning the monster years later Charlie posted a new 'sighting', and once Paul found a periscope picture Charlie e-mailed him telling him to stop researching. Agent Z later discovered Charlie's secret.