Jonathan Broom and his wife Deborah have put everything on hold while he pursues his dream of building a mini Hollywood Hills-style mansion right in the gritty heart of north London. For ten years Jonathan Broom has been obsessed with building his own home.They finally stumble across a scrap of land right in the gritty heart of North London, but it's fraught with problems, and the only way they can build their wildly ambitious £1million pound family home, complete with nanny flat and swimming pool, is by sinking half of it six metres below ground. It's a project that pushes the couple and their builder to the very limit. Desperate to make every penny of the budget stretch, Jonathan strikes every deal he can, and even sells his business to raise funds. Originally scheduled to take a year, this giant hole in the ground consumes their money and lives for much longer.