The Country House Revealed: A Secret History of the British Ancestral Home, By Dan Cruickshank

Dan Cruickshank is a well-connected and charming man; he also takes an interest in old buildings.

This makes him, in the eyes of TV executives, the go-to man for presenting luscious documentaries about architectural history – the poshest form of property porn.

This handsome book accompanies Cruickshank's new BBC series, and could have been destined for the coffee table. Happily, someone had the sense to make it a size that means you can actually read it. Inside, Cruickshank promises to "reveal the secret history of the British ancestral home", which is an audacious claim, given that Country Life has been doing that every week for over 100 years.

Never mind. This is porn, and the formula is simple: Cruickshank takes six important houses and tells their stories. What makes them "secret" is that none is open to the public (which is where his good connections come in). To be fair, it's a shrewd selection: between them, they represent the key periods of design, ranged across England, Northern Ireland and Scotland.

He starts with South Wraxall manor, an unmolested Tudor gem, notable for having a "death room" attached to the Great Hall. This was where enlightened members of the Long family could ponder their mortality, in between slap-up banquets and commissioning some of the finest chimneypieces of Elizabethan Britain.

Next is Kinross House, inspired by the French chateau Vaux-le-Vicomte; then Easton Neston, the Baroque pile recently sold by Lord Hesketh to the fashion tycoon Leon Max; Wentworth Woodworth, the biggest privately owned house in Britain; Clandeboye, a 19th-century Guinness pile; and Marshcourt, the Lutyens masterpiece, which the Labour MP Geoffrey Robinson rescued in the 1980s.

A lot of ground is covered and, as with all buildings, the human stories are often as interesting as the nid-nodding over spandrels and groin vaults. (There's a handy glossary at the end.) The promised revelations are, though, disappointingly few. Marshcourt is famous for its chalk billiard table, on which players can chalk their cues; some say it was carved out of the hillside, but after airing the theory, Cruickshank feebly concludes that we shall never know. He also captions a photo of Marshcourt's "curious" outbuildings, without acknowledging their significance as among the earliest purpose-built garages in Britain. He is lazy, too, in his use of the word "incredible" – these houses are impressive, but nothing in domestic architecture is ever beyond belief.

Perhaps the most telling revelation is the acknowledgments page. Here we learn that Jonathan Parker "researched each of the country houses featured in the book and television series, and drafted the chapter on Marshcourt". Otto Saumarez Smith also drafted a chapter, and two other researchers are named. You have to wonder what was left for Cruickshank to do, apart from choose the font size in which his name is embossed on the cover.