Markus Andarius Thul was a male Human individual, affiliated with the House of Thul. He existed during the eras of the Cold War and the Alderaan Civil War.
Prior to the outbreak of the Alderaan Civil War, Markus Thul held a position of power and displayed loyalty within the House of Thul. Before his family returned to the planet of Alderaan, Markus embraced the support offered by the Sith Empire, expressing confidence that his family would successfully seize control of his homeworld's throne.
As years of fighting passed, Markus started to feel skeptical about the alliance with the Empire. He also began to worry that House Thul was going astray by simply following the Imperials' commands.
In the year 3643 BBY, Markus spearheaded a mission, leading a team of Imperial commandos in a covert attempt to infiltrate Castle Organa. This plan, however, failed, resulting in his capture by Captain Balic Cormac of House Organa. Subsequently, Markus was imprisoned and subjected to interrogation.
Later, he received a visit from the new lieutenant of Havoc Squad, dispatched to locate former Havoc Squad member Gearbox. While Markus possessed knowledge of Gearbox's whereabouts, he pleaded with the lieutenant to ensure the safety and rescue of his wife, Altana, and daughter, who had been betrayed by the Empire, promising to reveal the truth in exchange. The lieutenant consented to safeguard his family from harm. The lieutenant successfully infiltrated House Thul and rescued Markus's wife and daughter. They were safely transported to House Organa, where they were reunited with Markus. Expressing his gratitude to the Havoc lieutenant, Markus provided the requested information regarding Gearbox and his location. Following the lieutenant's authorization for their release, Markus vowed that he and his family would forever be indebted to the Havoc lieutenant. Subsequently, he and his family left Alderaan and relocated to Chandrila.