Saving Lives at Sea will restore your faith in humanity – but might put you off sandy beaches

Little fazes or bemuses the utterly professional volunteers. In one rescue in Blackpool, a woman experiencing mental health problems is pulled from the water. “I’m going to Jesus!” she says, once she’s safely aboard the RNLI dinghy. “We told her, you know, we can’t take you to Jesus,” recounts Danny, “but we can certainly take you back to shore.”

In another incident, in London, the crew must wrestle with two naked, muddled young men who have jumped into the Thames. “I feel dry!” one cries – yes, because you’re in a boat now with a towel round you, comes the patient reply.

The high seas bring high drama, too; helmet cams provide immersive, pulse-quickening footage of the deceptively slight-looking orange dinghies contending with crashing waves, stranded walkers and struggling swimmers – and there is not always a happy ending.

But, as is always the case, it’s the human element that proves most fascinating. We hear not just from those who are rescued – looking much neater, and drier, than when we first encounter them – but also from the volunteers, who, inevitably, have plenty of tales to tell.

Take Alan, a school caretaker, who’s volunteered for the RNLI in Eastbourne for 15 years. In 2012, he was commended for his actions during one particularly difficult call-out, to Beachy Head. A man had driven his car off the cliff; the beach he landed on had been cut off by the tide. Alan swam in to reach what he thought would be a dead body – but the man was still alive. As Alan describes that night to the programme-makers, his mother, who he lives with, listens nearby – it’s the first time she’s heard him speak about it.

We also see the lovely way that history and community gather around a lifeboat station like barnacles; how for many, it becomes a way of life. In the first episode, current volunteers at Mumbles Lifeboat Station near Swansea remember the loss of eight crew during an attempted rescue in 1947; it’s clear the tragedy is still strongly felt seven decades later.

And in Cornwall, fishmonger Gareth (“Have you lived in Newquay all your life?” “Not yet!”) describes his lifesaving pedigree – his great-great-grandfather was on the very first outing of the Newquay lifeboat in 1864.

Be warned: this absorbing, moving series does have a couple of side effects, one more welcome than the other. Yes, it will restore your faith in humanity, and in the sheer grit and courage of ordinary people – but a sunny, sandy beach may not look so inviting.

Saving Lives at Sea begins on Wednesday at 9pm on BBC1