When a virus spreads through the hospital, six babies in the maternity unit are infected. Dr. House and his team must make some very difficult decisions.
The burden falls to Locke to stop the island's shifts through time. Meanwhile, Ben's attempts to reunite the Oceanic Six are proving unsuccessful.
Kate discovers that someone knows the truth about her `son's' parental lineage. Meanwhile, the castaways feel the effects of the time-shifting island.