Marcus has always been a straight A student but has a tendency to substance abuse since his teenage years (always keeps functioning though). As a kid he had to go hunting with his father though he always hated it. Still it gave him an appreciation for nature and although he didn't go hunting anymore when he was older he always enjoyed outdoor activities like camping, climbing and eating magic mushrooms in the woods.
After school he travelled did some odd jobs here and there and spent a year working in a bar in Manchester/ England until after another 3-day drinking binge he decided to go back to Germany and study medicine in the small university town Goettingen. Having finished the pre-clinical exam he specialised in infectious diseases at Max- Plank Institute. So he followed in the footsteps of his father Dr Friedrich Hansen who is one of the most influential scientists in the field of infectious diseases and vaccinology.
Shortly after the outbreak Marcus went to Chapaevsk Base with his father and a delegation of "Doctors without borders" (medecins sans frontieres).
On the 19th of July, two days after they had arrived at Chapaevsk, they put together a team of scientists and doctors guarded by some UN soldiers and decided to go north. The plan was to find the causation of the disease, identify the pathogen and ultimately find a vaccine/ cure.
It didn't take long until they were attacked by a horde of infected.
He regained consciousness a few days later. A group of people who called themselves "The Sancuary" had found him in the wreckage of a humvee by the roadside and realized that he was still breathing. After a heated discussion about whether they should just end his misery or try to save him they had finally decided to carry him to their camp tend to his wounds...