The Tempest (Star Trek Deep Space Nine, No 19)

When a ferocious plasma storm strikes the entire Bajoran system, Deep Space Nine becomes a port under siege, filled to overflowing with stranded space travelers, unpredictable aliens, and Klingon smugglers. Worf and Odo find themselves tested to the limit as they struggle to control the chaos that has consumed the station.
But even greater danger faces Dax and botanist Keiko O'Brien when they must fly a runabout into the very heart of the storm -- and encounter a strange new form of life!