Just reprinted by Sourcebooks Casablanca in December. It was originally published in 1928 and is set in the mid 18th century.

Here's a synopsis of the book: In an age of slippery politics, Robin and Prudence Tremaine, the children of the notorious and brilliant Viscount of Barham, find themselves on the wrong side of the Jacobite rebellion. The Viscount sends his offspring on the road to London, each masquerading as the opposite sex.

In her guise as a young gentleman, Prudence attracts a mentor in Sir Anthony Fanshawe, who soon uncovers her true identity and becomes an accomplice in their escape. Robin and Prudence rescue the lovely Letitia from an unwanted elopement, and Robin, disguised as a lady, becomes her confidante. The plot unwinds with a great deal of adventurous doings—sword fights, narrow escapes, blackmail, and highwaymen—until Robin must reveal his true identity and woo Letitia in earnest. But when she finds out the truth, will she accept an adventurer for a husband? Or will his masquerade be Robin's undoing?

Masqueraders $9.99 "A treasure beyond price. The Masqueraders is a wicked delight, worth more than its weight in gold."-Anne Stuart Such a daring escape-Their infamous adventurer father has taught Prudence Tremaine and her brother Robin to be masters of disguise. Ending up on the wrong side of the Jacobite rebellion, brother and sister flee to London, Prudence pretending to be a dashing young buck, and Robin a love...

You may also be able to pick up a copy on eBay:

The Masqueraders by Georgette Heyer (2009, Paperback... $8.35

1930s? Georgette Heyer 'The Masqueraders' with Jacket $8.89

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Masqueraders-Georgette Heyer $11.77

The Masqueraders - Georgette Heyer, first Austr Edition $13.40

The Masqueraders NEW by Georgette Heyer $16.51

Masqueraders: Georgette Heyer [Paperback 975123 $27.17

Masqueraders: Georgette Heyer: Arrow [Paperback 975127 $24.73

Masqueraders (New edition) by Georgette Heyer | BRAND N $13.75

Masqueraders - Georgette Heyer - NEW BOOK $15.12

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