“Extreme Measures” is episode twenty-three of season seven of Star Trek: Deep Space Nine.
In the previous episode, “Tacking into the Wind”, the progress of Odo’s disease had accelerated to the point where he had appeared to be dying. This episode opens with Dr. Bashir narrating his medical log. Odo, Garak and Kira have returned to the station, but Julian has failed to make any progress on a cure for the disease.
Odo wants to know how long he has left to live. Bashir doesn’t want to come straight out and tell him, but when Odo presses, he does. One, maybe two, weeks. Odo then speaks to Kira and tells her to return with Garak to Damar’s base. Kira wants to stay, but Odo says that Damar has no real experience in running a resistance organisation. Plus, Odo doesn’t want Kira to see him die as she watched Bareil die in “Life Support”, and in the same place. O’Brien has examined the Breen energy dampening weapon and has sent the specs on to Starfleet.
O’Brien decides that he and Julian need to tell Sisko that they have sent a false message to Starfleet Medical saying that Julian has found a cure for Odo’s disease, in order to lure an operative from Section 31 to the station. Sisko wants to know what good that will do, so Julian tells him that Section 31 probably infected Odo in the first place. Sisko is not that happy to have been kept in the dark, and also wants to know why an operative would give them the cure anyway. It seems that Bashir has got an – illegal – Romulan memory scanner to help with this. Bashir is not happy how many people must have been involved in Odo’s infection – dozens – and would like to destroy Section 31.
Sloan arrives on the station to tell Julian he has a new mission. Julian was prepared and captures Sloan in a containment field before stunning him. As Sloan is being set up to have his mind scanned, Julian tells him what he’s doing – so Sloan attempts to commit suicide.
Although Dr. Bashir is able to prevent Sloan from dying, his mind has been badly damaged, making the memory probes useless. Plus, he will die in about an hour anyway. So Julian comes up with a new idea – get inside Sloan’s mind and look through his memories for the cure. Which is dangerous, and potentially fatal.
O’Brien accompanies him – partly so he doesn’t have to explain what is going on to Sisko – and they find Sloan. An unusually cooperative, and rather repentant Sloan. Which makes it look like it’s going to be easy to find the cure. Of course, it isn’t.
There are some funny bits where Julian and Miles are talking about their friendship.