Alias il santo

Professor Smith-Smyth-Smythe of Timbuctoo was a firm believer in the cheerful hospitality of the English countrside, until he registered at the Beacon Inn, where he was drugged and otherwide treated with deliberate disdain. Of course, the fact that he was Simon Templar, The Saint, might have had some effect on the temperature of his welcome.

"Story of a Dead Man"
"The Impossible Crime"
"The National Debt"
(Some editions contain "The National Debt" and "The Man Who Could Not Die" from the previous book).