Expecting Amish tells the story of Lancaster, Pennsylvania Amish model boy Samuel, who is devoted to his arranged betrothed, Hannah Yoder.
Hannah reaches 18 and decides to join a few peers, like Isaac, on Rumspringa, the traditional taste of wicked life outside, in this case in LA.
She's the only one who doesn't seem to enjoy the trappings of modern free youth and avoids parties, but is charmed by Josh, a more mature young intellectual, who shows her the simple joys of modernity.
They become lovers, but unlike Isaac, she doesn't simply stay behind but insists on parting properly with her family and Samuel.
Once home, she finds it too hard, so after weeks, during which only Samuel finds out she's pregnant and offers to pretend being the father, Josh comes to demand a decision.