A woman plunged into the sea on a Royal Caribbean cruise and was rescued after desperately clinging to a lifebuoy for 20 hours near a Greek island, according to the Hellenic Coast Guard.

The 44-year-old El Salvadoran passenger went overboard on the Odyssey of the Seas ship — and was found conscious in the Ionian Sea near the island of Zakynthos on Friday, Greece’s Ministry of Foreign Affairs said, according to USA Today.

Footage shows the dramatic moment the Hellenic Coast Guard pulled her to safety in the dark waters. Officials then rushed her to hospital for a medical examination.

It was not immediately clear how she plunged overboard.

The tourist had left for a week-long cruise that departed from Civitavecchia, Italy, on Oct. 4.

An investigation is ongoing.

Royal Caribbean didn’t immediately return a request for comment.