Pallid, unlifelike Regency romance--featuring gorgeous young Lady Georgianna, who (disguising herself as her twin brother) hides her horse-riding prowess from the visiting Marquis of Willerton. . . because she thinks he'd prefer a ""demure young miss"" as a wife. In fact, of course, the un-stuffy Marquis is overjoyed when he learns of Georgie's secret gifts (she's also a good shot)--so there'll be wedding bells as soon as a few subplots get straightened out: Georgie's twin brother George runs afoul of evil Sir Montague, a jewel thief who takes revenge by blackmailing and nearly raping Georgie (she fends him off with a pistol); Georgie's older brother John (the Earl of Danver) relaxes enough to woo Lady Barbara, a free-spirited neighbor; and when John is hurt by one of Sir Montague's dirty tricks, Georgie must ride a wild horse to summon the doctor. Tepid plot, dialogue that's either stilted or anachronistic (""'I'm in real trouble,' groaned George"")--weak tea, even by those undemanding Regency standards.