The Winter Garden by Nicola Cornick

Sweeping across generations from the 1600s to the present day and inspired by the true story of the leader of the infamous Gunpowder Plot, Nicola Cornick’s latest historical mystery combines past and present story lines that fans of Philippa Gregory and Susanna Kearsley will devour.
1605: Anne Catesby fears for her family. Her son, the darkly charismatic Robert, is secretly plotting to kill the king, placing his wife and child in grave danger. Anne must make a terrible choice: betray her only child or risk her family’s security…and her very life.
Present Day: When her dreams of becoming a musician are shattered, Lucy takes refuge in her family’s ancestral home in Oxfordshire. Everyone knows it was originally home to the notorious gunpowder plotter Robert Catesby. As Lucy spends more time in the beautiful winter garden that Robert made, she starts to have strange visions of a woman in Tudor dress, terrified and facing a heartbreaking dilemma.
As Lucy’s and Anne’s stories converge, a shared secret that has echoed through the centuries separating them will change Lucy’s life forever…