Maggie MacLaren longs to leave her home town, even if she must quell her attraction to rugged steelworker Jake O'Neill. When Andrew Adair walks into Maggie's library, he sweeps her into his world of wealth and power, where at last dreams seem possible. However, Andrew's world is not all it appears to be. High above town, reclusive young widow Allison Kimball arrives at her wealthy family's mountain resort home to find tucked into her carpetbag a love letter. So begins a series of secret epistles and midnight trysts with a man known only by his cryptic signature, "D." Their love story unfolds to reveal a truth that will threaten to tear them apart as their world comes crashing down in the Johnstown Flood of 1889.