The Underground Man (1997) is a novel by Mick Jackson. Critically acclaimed, it was shortlisted for the Booker Prize for that year. It shows the life of an eccentric and reclusive Victorian Duke, loosely modelled on William Cavendish-Scott-Bentinck, 5th Duke of Portland. His latest scheme involves building a set of tunnels beneath his estate.
Mick Jackson has recently written a book about building a set of tunnels under his home.
The paragraph states his latest scheme involves building a set of tunnels beneath his estate, not that he's writing a book about it.