Thrilled by Oliver's naughty suggestion to perform late-night naked sex on a hotel balcony, Cate ignores his moody indifference after the event. Apparently, he has a lot on his mind; but intercepting a cryptic text meant for someone else sparks her suspicion. Worried her handsome, younger husband is up to no good - but scared of finding out - Cate decides there must be a reasonable explanation. However, when best friend Sam unearths some damning evidence she's compelled to dig deeper. Torn between trust and doubt she hunts for signs of betrayal, concocting a shameless web of lies in an attempt to reveal the truth. Still unconvinced, she recruits a neighbour to spy on Oliver at work, but has she accidentally unleashed a monster? Strange Mr Ball hides a secret passion...and he'll go to any length to get what he wants. Reasonable doubt is more 'hen' than chick-lit; a barefaced contemporary exploration of a forty-plusser's fears and dreams. Ambitious student and part-time online supermarket shopper, Cate Cooke, faces up to her worst nightmare, colliding with obstacles along the way as she turns detective, and examines the clues.