In the future, Julia and Caleb dig up Alan’s grave and make a discovery that only adds more questions about the plague. Evidently Alan left a clue in the mismatched bones in his grave, instead of just a note, because why make anything simple when trying to deadly contagion ? In the present day on the island, a plague ridden child appears in the "safe haven" and then is mysteriously healed, prompting much WTFing from the team. Meanwhile, Sarah and Alan have a (see episode name) and we discover the horrifying truth of what happened to their baby. Seriously, any women who saw this episode are probably having nightmares.