When David Yarrow was sent to the heart of Africa to photograph lions in the wild, he spiced up the job with the help of some aftershave.
The self-taught photographer used the smell to attract the animals to his remote cameras to take his pictures.
Explaining how he took the picture of a lioness in Kenya, called The Prize, he said: "The placing of remotes at sunrise is a low-percentage and dangerous pursuit near lions.
"After some unsuccessful mornings, we covered the camera casing in Old Spice stick aftershave, as my guide knew that lions were attracted by that smell because the local Masai and indeed colonialists have worn it for years.
"It worked, and the lioness came straight towards the camera against a clean backdrop. A second after this image was captured, the lioness took the camera casing in her mouth and walked 700 yards into the bush."
The black-and-white images, which also include another picture of a lion relaxing shortly after killing and eating its prey, will be unveiled when Mr Yarrow delivers the inaugural Tusk Conservation Lecture at Christie's in London tonight.
He said: "This lion had just killed and eaten and his demeanour is both sated and content. But he is alert - his right eye is very telling and grabs our focus in the picture.
"Looking at this image, it's almost hard to believe the king of the food chain in Africa could be under such threat. In the last 15 years, the Kenyan lion population dropped from over 15,000 to less than 2,000 - with 100 lions lost every year.
"At this rate, the lion could be extinct in Kenya within 20 years. My job with Tusk is to highlight the need for action now with powerful, emotive imagery of these extraordinary animals."
Mr Yarrow gives 10% of his photography sales to Tusk, whose patron is the Duke of Cambridge.
Twenty-five years ago, 200,000 lions roamed across Africa, but today that figure has shrunk to as few as 20,000, of which only 3,500 are adult males.