The idea is that they would accept applications from around the world for the mission and select a crew, then train them and send them to Mars. Once there, the crew would attempt to establish a permanent colony with the knowledge that they are not coming back home. Ever.
A mission like this costs a lot of money, but the company involved plans to raise a lot of it through advertising. What kind? The kind you see on TV. Specifically the reality TV show following their journey. That's right, the entire mission is meant to be televised as a reality TV show. So I was joking around with friends and spinning a yarn of one scenario that could unfold.
Once the crew arrive on Mars and start setting up their facilities, after a while they notice that a crew member has mysteriously disappeared. They never find the person. Weeks go by and another member disappears. This evolves and it becomes clear that something is responsible for their disappearance, etc. Then, just as we think the remaining crew are in crapola up to their necks, they come on TV and collectively yell "Psyche!", showing that nothing actually happened.
Or, even better, we find out by the end that the crew never actually went to Mars. They're filming from the Mojave desert.