Stardate 52645.7: With Odo knocking at death's door, scant time remains to find a cure. In an effort to lure Section 31 out of hiding to obtain the vaccine, Doctor Bashir and Chief O'Brien have gone behind Captain Sisko's back. Now, telling him about their plan, Doctor Bashir informs Sisko that Section 31 is the only hope that Odo has left.