On assignment in Vienna; photographer Ian Jarrett falls desperately in love with a woman he meets by chance; Marian Esguard. Back in England; he breaks up with his wife and goes to meet Marian at an agreed rendezvous. Marian fails to show. Searching desperately for her; he stumbles on a Dorset churchyard full of the gravestones of dead Esguards. He also meets a psychotherapist; Daphne Sanger. She too is looking for someone: a former patient who has come to believe she is the reincarnation of Marion Esguard; who lived in Regency times and; it emerges; may have invented photography ten years before Fox Talbot. But if so; why is she unknown to history? And where is the woman he met in Vienna? Ian sets out to solve a mystery that may be 170 years old. At the end of his search a trap awaits him. There is a twist at the end of Caught in the Light that is Robert Goddard's most cunning to date.