False Colours (by Georgette Heyer)

(Amazon UK link)

'False Colours' is a historical novel by Georgette Heyer.

Kit returns home from abroad to find his identical twin brother missing. He takes his brother's place to save embarrassment, and finds himself having to continue the part...

It's an ingenious albeit slightly unlikely plot, made believable by the delightful and well-developed characters and conversation, with a charming conclusion.

I'd read this before two or three times and enjoyed it just as much this time.

Highly recommended.

A longer review of 'False Colours' can be found here, after yet another re-reading some years later.