Sarah plays Charlotte, who discovers the night before her wedding that her fiancé Tom was once accused of a shocking crime.
She loves Tom, but with the clock ticking, her doubts begin to grow, she starts to wonder if she really knows him as well as she thinks. Can she trust him at all?
Will Charlotte go ahead and marry him, knowing he has a suspicious past she knows nothing about? Can she really see her future with this man?
The Secrets, BBC1, 10.35pm
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