Hospital Ship ends with Ha Ji Won's return.

Song Eun Jae (played by Ha Ji Won) gets cured from osteosarcoma (a type of bone cancer that begins in the cells that form bones) and lives happily with Kwak Hyun (played by Kang Min Hyuk)

In the last 2 episodes, Eun Jae suffers from severe leg pain whereby the symptoms have worsened to such an extent that she couldn't stand for a long period of time. She made a CT scan with the recommendation of Nurse Yoo Ah Rim (played by Kwon Min-ah). The results turned out to be shocking where she was diagnosed with aggressive malignant tumour from the bone and causing the pain. 

                 

Eun Jae was worried whether she should reveal this truth to Hyun so she started avoiding him. Some kind of noble idiocy! AGAIN! It was a perfect timing where Eun Jae receives a letter from London Emergency Medical Center and is pondering about it. Hyun tells her what she is hesitating about as this is a lifetime opportunity. 

After spending an entire day and night with Hyun, Eun Jae left and disappeared. The cancer cells started to spread to her lungs with survival rate is low. Eun Jae suffered on her own and Hyun found out about it a month later. In tears, she tells him to get lost and to leave her alone. She does miss her elderly patients waiting in those remote islands. Patiently Hyun sends her a text stating to come back to fight this illness together. He can't do everything by himself without her help.

Again in tears, Eun Jae hugs Hyun for encouragement to undergo the surgery at the hospital.
After the surgery and recovery, Eun Jae returns back to work. The Hospital Ship sets sail again to remote islands to service the elderly and sick people. Together happily with Hyun, Eun Jae is feeling all good and stable again.

Hospital Ship is a drama depicting generations of empathy that doctors who have different stories while carrying out medical activities by boat on an island as infrastructure is lacking, The young doctors learn and matured further to communicate with sincerity to the island villagers.
It was a fresh interesting medical drama which took the first spot when it first aired. Its ranking began to slide down after SBS's While You Are Asleep starts to air simultaneously. With great realistic acting from Ha Ji Won and supporting casts- this cannot be replaced by the rookie actors.