Operation Downfall was the proposed Allied plan for the invasion of Japan near the end of World War II.
 The planned operation was abandoned when Japan surrendered following the atomic bombings of Hiroshima and Nagasaki, the Soviet declaration of war and the Soviet invasion of Manchuria.
 The operation had two parts: Operations Olympic and Coronet.
 Set to begin in November 1945, Operation Olympic was intended to capture the southern third of the southernmost main Japanese island, Kyūshū, with the recently captured island of Okinawa to be used as a staging area.
 Later, in the spring of 1946, Operation Coronet was the planned invasion of the Kantō Plain, near Tokyo, on the Japanese island of Honshu.
 Airbases on Kyūshū captured in Operation Olympic would allow land-based air support for Operation Coronet.
 If Downfall had taken place, it would have been the largest amphibious operation in history.
The Battleship Island () is a 2017 South Korean period action fiction film starring Hwang Jung-min, So Ji-sub, Song Joong-ki and Lee Jung-hyun.
 It is a Japanese occupation-era film about an attempted prison break from a forced labor camp on Hashima Island.
Battle of Jeokjinpo was fought on 8 May 1592.
 After the Battle of Happo, further reports of an additional 13 Japanese ships prevented Yi Sun-sin and his fleet from resting long on the morning of May 8.
 Admiral Yi once again ordered his fleet to pursue the Japanese in the direction of Jinhae.
 The Korean forces caught up with the Japanese ships at Jeokjinpo, but the Japanese officers and crew abandoned their ships and fled into the mountains before the Koreans could fire upon them.
 The Koreans easily sunk the 13 abandoned Japanese warships.
Midnight Runners (Hangul: 청년경찰 ; Hanja: 靑年警察 ; RR: "Chung-nyeon-gyung-chal "; lit.
 Young Cop ) is a 2017 South Korean action comedy film directed by Kim Joo-hwan and starring Park Seo-joon and Kang Ha-neul.
 The film was released on August 9, 2017.
Confidential Assignment (; lit.
 Cooperation) is a 2017 South Korean action film directed by Kim Sung-hoon.
 It stars Hyun Bin, Yoo Hae-jin and Kim Joo-hyuk.
The Villainess is a 2017 South Korean action thriller film directed by Jung Byung-gil, starring Kim Ok-bin.
 The film had its world premiere at the 70th Cannes Film Festival in May 2017.
Hashima Island (端島 , or simply Hashima — "-shima" is a Japanese suffix for "island" ) , commonly called Gunkanjima (軍艦島; meaning Battleship Island), is an abandoned island lying about 15 kilometers (9 miles) from the city of Nagasaki, in southern Japan.
 It is one of 505 uninhabited islands in Nagasaki Prefecture.
 The island's most notable features are its abandoned concrete buildings, undisturbed except by nature, and the surrounding sea wall.
 While the island is a symbol of the rapid industrialization of Japan, it is also a reminder of its dark history as a site of forced labor prior to and during the Second World War.
Our Diary is a 2017 South Korean action drama film directed by Lim Gong-sam.
Part-Time Spy (, lit.
 "Temporary Special Forces") is a 2017 South Korean action comedy film starring Kang Ye-won and Han Chae-ah.
 It was released on March 16, 2017.
Fabricated City (Hangul: 조작된 도시 ; RR: "Jojakdoen Doshi "; lit.
 Manipulated City ) is a 2017 South Korean action thriller film directed by Park Kwang-hyun and starring Ji Chang-wook, Shim Eun-kyung and Ahn Jae-hong.
 The film was released on February 9, 2017.

Question: Which abandoned Japanese island appeared in the 2017 South Korean action film "The Battleship Island" ?
Answer: Hashima Island