Would you marry a complete stranger?

That is the simple yet completely complicated question Married at First Sight poised to six singles and viewers back in 2014. Since then, 18 couples have signed up to have their marriages documented over the course of eight weeks, with three new pairs set to kick off their journeys when season seven, set in Dallas, premieres Tuesday on Lifetime.

Based on a Danish format, MAFS sets out to stage the ultimate relationship experiment, seeing if "the parenthesis of already starting the relationship with marriage would change the way people acted and impact the investment in that union," Dr. Pepper Schwartz, one of the show's three experts, explained.

But if you think Married at First Sight really begins simply with two strangers agreeing to say "I do," the road to the altar is a lot longer and bumpier than you could imagine.