Author
Calum Marsh
Calum Marsh's next book, The Glass Box, releases October 27, 2026.
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About Calum Marsh
The Glass Box: An eye-opening and wildly entertaining book about the multimillion-dollar fitness phenomenon CrossFit and its mercurial founder, Greg Glassman—from an investigative journalist and regular contributor to the New York Times. How did an upstart workout regimen, begun out of commercial gyms in Santa Cruz in the ‘90s, become one of the most popular and polarizing fitness platforms in the world? And who, exactly, is the person responsible for its success?
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Upcoming Titles
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The Glass Box
October 27, 2026 View on Amazon
An eye-opening and wildly entertaining book about the multimillion-dollar fitness phenomenon CrossFit and its mercurial founder, Greg Glassman—from an investigative journalist and regular contributor to the New York Times. How did an upstart workout regimen, begun out of commercial gyms in Santa Cruz in the ‘90s, become one of the most popular and polarizing fitness platforms in the world? And who, exactly, is the person responsible for its success?
Earlier Books
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True Lies
October 6, 2026 View on Amazon
A provocative, eye-opening look at a genre long dismissed as trash television. Featuring interviews with dozens of reality hosts and stars, including Jeff Probst and Gordon Ramsay, and with insights into its history, production, and ethics, True Lies will change the way you look at reality television forever. When Survivor premiered on CBS in the early summer of 2000, it seemed like a cut-and-dry novelty: interesting, and immensely popular, but almost certainly doomed to be short-lived.