 Sixteen years before Oceanic 815 crashes on the island , Rousseau was a heavily pregnant member of a six @-@ person crew aboard a French research vessel three days out of Tahiti . The crew picked up a radio signal emanating from the South Pacific , which was a repeating set of six numbers : 4 , 8 , 15 , 16 , 23 and 42 . While attempting to find the source of the signal , the ship ran aground on rocks surrounding the island . Before reaching the shore , Rousseau and her team found Oceanic 815 survivor Jin @-@ Soo Kwon ( Daniel Dae Kim ) in the water , who had been time @-@ travelling as a result of the time shifts which had been moving him and the flight survivors through the island 's history . 
