The conditions were so fierce that the first helicopter winchman hoisted down had their boots torn off and had to be checked over in hospital.
The alarm was first raised by a 999 call to HM Coastguard at about 6.10pm on Monday 22 May with a report of two young adults caught by the tide on a rock and calling for help 30 metres from the shore in Bassets Cove, near Portreath.
Before they could be reached, however, they were swept off by the waves.
Portreath and St Agnes Coastguard Rescue Teams were sent to the scene, along with the RNLI’s all-weather and inshore lifeboats from St Ives and the inshore lifeboat from St Agnes.
Coastguard Rescue Officers attempted an in-water snatch rescue, which was unsuccessful as were throw lines, due to the difficult conditions.
The woman was thrown a life jacket and told to put it on, just as she was swept into the cave.
The Coastguard helicopter was despatched from Newquay and winched up the man who was quickly flown to the Royal Cornwall Hospital in Treliske.
The winchman was also admitted to A&E after being so battered about during the rescue that their boots were torn off.
Retrieval of the woman proved even more complicated as her location was hard to see amid the spray and poor light, and the tidal conditions were too dangerous for a rescue.
A police drone assisted Coastguards to float a torpedo rescue buoy into the cave for the woman to grab, if she was able.
In an effort to locate her, a winchman was lowered close to the mouth of the cave several times by a second Coastguard helicopter sent from St Athan, Wales.
The falling tide finally opened a window to reach the woman, enabling the helicopter and Coastguard cliff rope teams to work together to drop a winchman and a Coastguard Rescue Officer into the cave to find the cold and shocked casualty.
The woman was ultimately recovered by 10pm after a nearly four-hour operation. She was winched into the helicopter and flown to the Royal Cornwall Hospital.
Both casualties survived. The winchman was released from hospital later that night.
Devon and Cornwall Police and the South Western Ambulance Service also attended.
Senior Coastal Operations Officer Marc Thomas said: “This was a courageous effort from everyone involved and ended successfully with the two people being retrieved from an incredibly dangerous situation.
“The layout of the cave funnelled the waves in, magnifying their power and creating potentially lethal conditions both for the casualties and the rescuers.
“The crews worked together with professionalism, teamwork and bravery to overcome the awful conditions and save two young lives.”
Marc added: “This near-miss is another reminder for everyone to be aware of the tides when visiting the coast and, if you get in trouble, to call 999 and ask for the Coastguard.”
