John Tagholm was born in Cardiff where he remained just long enough to be christened in Llandaff Cathedral. Then followed five years in Hull before moving to London where he has been ever since.
After leaving the University of Kent he responded to a newspaper advertisement which would now be considered non-pc: ‘Children’s writer needs assistant. Pipe-smokers and those with beards need not apply.’ He was neither and so became Hawk-eye to Big Chief I-SPY, the writer of the famous series of factual books for children. Within weeks he was writing the regular I-SPY column in the Daily Mail and went on to produce several of the books, including I-SPY Football, Cricket, At The Airport, Birds, Foreign Coins and Cats, a valuable grounding for the world of fiction writing which was to follow later.
After spells at the IBA, the Independent Broadcasting Authority (now Ofcom), John joined Thames Television in 1976 and stayed for thirteen years, working first in sport and then in the documentary and features department. For several years he was programme editor of the pioneering daytime programme, Afternoon Plus which later transferred to Channel 4 as Mavis on 4. When Thames lost its franchise he formed Pineapple Productions and became an independent producer, making programmes for the BBC, ITV and several of the newly emerging digital channels.
He has written all his working life, for newspapers, magazines, radio and television. There was a long gap between Football: How Much Do You Really Know?, published by Independent Television Books in the 70s and No Identifiable Remains, his first work of fiction. Bad Marriage, though, followed quickly with Parallel Lives close behind. A Girl Called Flotsam was published in 2017. elsewhere, his first non-fiction was published in 2013.
The Value of Nothing was published in October 2019.
From the Author
If I appear in my fiction at all, it is unwittingly. I am the eldest of four brothers, the father of three sons and the grandfather of four grandsons, Darwin, Hunter, Lucas and Marlow. In a male-dominated life, I am particularly interested in the role played by women. 
I’m not sure into which category my books fall although I have always thought they are not so much whodunits as whydunits. Excusable crime interests me, as does crime committed by women and I am constantly surprised at how real life is more bizarre and unbelievable than fiction.
Writing for television and radio demands precision and brevity, as did my early I-SPY columns, which had to be contained in 500 words. This is an invaluable background for fiction, a discipline which leads to the discarding of anything not absolutely necessary to the story. Regular essentials are France and the River Thames. I walked across France, from Sangatte to St Tropez, to celebrate my fiftieth birthday. My account of this strange and memorable adventure was published sixteen years later as elsewhere.
The Thames has been an abiding passion ever since I began working opposite what used to be Puddle Dock in Blackfriars in the winter of 1969. The river and its environs play a crucial part in A Girl Called Flotsam. The Value of Nothing is set in the Paris very few visitors ever see, behind the great railway termini, well out of sight of the golden facades of what most people regard as the world’s most beautiful city.