All that I am by Anna Funder: (summary from Goodreads.com)
Two years after Hitler came to power in Germany, the bodies of Dora and her friend Mathilde, prominent anti-Hitler activists in exile, lie poisoned in a flat in Bloomsbury. The room is locked from the inside; the place appears undisturbed. As London buzzes with rumours of Gestapo assassins operating on British soil, the inquest whitewashes their deaths as romantic suicides. All That I Am is the story of four extraordinary people who risked their lives to alert the world to Hitler. Two narrators, Ernst Toller and Ruth, tell the story of Dora, the woman they both loved. As we come to know them, and her, the novel reveals itself as a searing and intimate portrait of courage and its price, of desire and ambition, and of the devastating consequences when they are thwarted. Closely based on a true story, All That I Am brings to light a new and very early hero of the resistance in a beautifully written novel that speaks to both the head and the heart.