swimming from cuba to florida, of gliding across the surface in flat, calm seas. now 14 hours into her swim, very little is going as planned. the water is choppy, the current, surging. and a terrible pain in diana's shoulder is taking its toll. >> i think it's going to come out of its socket. >> but still she pushes through, driving her body forward. it's not easy. simply keeping her body fueled is a delicate balancing act. even getting her something to drink can be a challenge. handler john hennessey -- >> a special mix. we're looking for 20 ounces and she's been doing about 24, which is really good. >> he rigs a line to drop the pouch of fluid into the water. >> i'm blowing the whistle. you'll see it trailing by the strip there and she'll pick it up and drink out of it. >> now rehydrated, diana takes