When life gives you lemons, call your best girlfriends and whip up some lemon martinis. Such is the mantra for the Ladies' Society for the Conservation of Martinis, which was established after one fateful PTA meeting, when four young mothers - Lynne, Mary Kay, Beth, and Carol - discovered they had more in common than they ever thought possible. Meeting once a month, the women would share laughs and secrets and toast to their blossoming friendship with a clink of their sacred martini glasses. The Society was their salvation and refuge. Then, life-shattering circumstances forced the group to dissolve, and their once gratifying friendship faltered. Two years later, Lynne passes away suddenly, and leaves behind a simple request: that her old friends sort through her belongings. Reluctantly, the women reunite to rummage through her closets. Buried deep within Lynne's lingerie drawer is an envelope addressed to the Society. And inside they find a letter that reveals a shocking secret and a final wish that will send the women on a life-changing journey, proving that nothing is more powerful than the will of a true girlfriend - and maybe a good, strong martini.