French Leave. The "Weaver" series, #3

A most inconvenient marriage... Forced by bankruptcy and scandal into exile in France, Lord Waverly expects never to return to his homeland until, staggering home from a gambling hell in the wee hours of the morning, he encounters a young novice escaping from a convent. When she asks him to escort her to England, promising him that her English grandfather will reward him handsomely for her safe conveyance, Waverly reluctantly agrees.
Alas, he soon realizes the enormity of his task. When he delivers the irrepressible Lisette to her grandfather's home only to discover that the old man is dead, Waverly is left with no alternative but to offer her the protection of his name. And when he is unexpectedly reunited with Lady Helen Brundy, whose marriage precipitated his flight to France, Waverly begins to discover that his marriage of convenience is likely to prove very inconvenient indeed...