Behind the perfect pill lies a dangerous secret.

Roberta, Rosie, Sandra and Linda meet at college in the 70s and remain constant friends, despite life’s up and downs. When Linda suddenly dies in 2005, shock gives way to suspicion. Is Svelta, the slimming drug she had been taking, a wonder drug or a threat to life? The situation grows more complicated because Rosie’s husband developed Svelta, and as he falls under investigation, the friends start to uncover long-held secrets and betrayals, both personal and professional.

But the pharmaceutical industry is not yet finished with them. The growing elderly population in the UK has provided property developer, Dom Maxwell, with a great opportunity. His luxury retirement complex, Summerlands, has been a complete sell-out. Its impressive facilities include The Retreat, a state-of-the art medical centre, run by Professor Richard Hawley. Rosie’s and Roberta’s mothers move into Summerlands, when they can no longer live independently. They don’t know it, but they are now part of Project Avalon, a government initiative to save costs. As Marjorie’s health declines drastically, Rosie and Roberta have to face up to dark forces determined to supress the truth.