Charles Todd: Inspector Ian Rutledge Mysteries

• Main Characters: Inspector Ian Rutledge, a veteran of the First World War who has returned to the police force as a detective but is battling with "shell shock" (what would be called post-traumatic stress disorder today). 
• Setting: Mostly England, in the years following World War I.
• Bold type indicates a book I've read. 

"Charles Todd" is the pen name used by the mother/son writing team of Caroline and Charles Todd. 

1. A Test of Wills (1994) 
2. Wings of Fire (1998)
3. Search the Dark (1999) 
4. Legacy of the Dead (2000) 
5. Watchers of Time (2001) 
6. A Fearsome Doubt (2002) 
7. A Cold Treachery (2005) 
8. A Long Shadow (2006) 
9. A False Mirror (2007) 
10. A Pale Horse (2008) 
11. A Matter of Justice (2008) 
12. The Red Door (2009) 
13. A Lonely Death (2011) 
14. The Confession (2012) 
15. Proof of Guilt (2013) 
16. Hunting Shadows (2014) 
17. A Fine Summer's Day (2015) 
18. No Shred of Evidence (2016) 
19. Racing the Devil (2017) 
20. The Gate Keeper (2018) 
21. The Black Ascot (2019) 
22. A Divided Loyalty (2020) 
23. A Fatal Lie (2021) 
24. A Game of Fear (2022) 

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Nicholas Meyer: Sherlock Holmes Pastiche Series

• Main Characters: Legendary detective Sherlock Holmes and his friend and biographer John H. Watson, M.D.
• Setting: Mostly Victorian/Early 20th Century England, with occasional visits to other areas. 
• Bold type indicates a book I've read. 

1. The Seven-Percent Solution (1974)
2. The West End Horror (1976)
3. The Canary Trainer (1993)
4. The Adventure of the Peculiar Protocols (2019)
5. The Return of the Pharaoh (2021) 

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Charles Finch: Charles Lenox Mysteries

• Main Characters: Charles Lenox, Victorian gentleman and armchair explorer, who is also an amateur sleuth. Most of the books also feature his aristocratic wife Lady Jane. 
• Setting: Victorian England, mostly London and Oxford.
• Bold type indicates a book I've read.

1. A Beautiful Blue Death (2007)
2. The September Society (2008)
3. The Fleet Street Murders (2009)
4. A Stranger in Mayfair (2010)
5. A Burial at Sea (2011)
6. A Death in the Small Hours (2012)
7. An Old Betrayal (2013)
8. The Laws of Murder (2014)
9. Home by Nightfall (2015)
10. The Inheritance (2016)
11. An Extravagant Death (2021)

There are also several "prequels":

1. The Woman in the Water (2018) 
2. The Vanishing Man (2019) 
3. The Last Passenger (2020) 

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Susan Elia MacNeal: Maggie Hope Mysteries

• Main Characters: Maggie Hope, a British-born American math expert living in London during World War II, who works for British intelligence as a codebreaker and sometimes-agent in the fight against the Nazi menace. 
• Setting: Mostly England, with occasional visits to America and other locales. 
• Bold type indicates a book I've read.

1. Mr. Churchill's Secretary (2012)
2. Princess Elizabeth's Spy (2012)
3. His Majesty's Hope (2013) 
4. The Prime Minister's Secret Agent (2014) 
5. Mrs. Roosevelt's Confidante (2015)
6. The Queen's Accomplice (2016) 
7. The Paris Spy (2017) 
8. The Prisoner in the Castle (2018) 
9. The King's Justice (2020) 
10. The Hollywood Spy (2021) 

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Catherine Aird: Inspector Sloan

(Sometimes referred to as the Chronicles of Calleshire.)

• Main Characters: Detective Chief Inspector Sloan and his assistant, Constable Crosby
• Setting: The fictional County of Calleshire, England 
• Bold type indicates a book I've read. 

1. The Religious Body (1966)
2. Henrietta Who (1968)
3. The Stately Home Murder (1969) [aka: The Complete Steel]
4. A Late Phoenix (1970)
5. His Burial Too (1973)
6. Slight Mourning (1975)
7. Parting Breath (1977)
8. Some Die Eloquent (1979)
9. Passing Strange (1980)
10. Last Respects (1982)
11. Harm's Way (1984)
12. A Dead Liberty (1986)
13. The Body Politic (1990)
14. A Going Concern (1993)
15. After Effects (1996)
16. Stiff News (1998)
17. Little Knell (2001)
18. Amendment of Life (2002)
19. Hole in One (2005)
20. Losing Ground (2007)
21. Past Tense (2010)
22. Dead Heading (2014)
23. Learning Curve (2016)
24. Inheritance Tracks (2019)

Also these short story collections, featuring Sloan and Crosby:

1. Injury Time (1995)
2. Chapter and Hearse (2003) 
3. Last Writes (2014)

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Jerry West: The Happy Hollisters

• Main characters: The Hollister family, consisting of five children (Pete, Pamela, Ricky, Holly, and Sue), and their parents (John and Elaine)
• Setting: The city of Shoreham (as far as I know, no state is ever mentioned)
• Bold type indicates a book I've read.

The Happy Hollisters is a series of books for children, published by the Stratemeyer Syndicate (also the publisher of the Nancy Drew and Hardy Boys series), between 1953 and 1969. The series was written by Andrew E. Svenson, using the pseudonym Jerry West, and was illustrated by Helen S. Hamilton. 

1. The Happy Hollisters  (1953)
   
2. The Happy Hollisters on a River Trip  (1953)
3. The Happy Hollisters at Sea Gull Beach  (1953) 
4. The Happy Hollisters and the Indian Treasure  (1953) 
5. The Happy Hollisters at Mystery Mountain  (1954) 
6. The Happy Hollisters at Snowflake Camp  (1954) 
   
7. The Happy Hollisters and the Trading Post Mystery  (1954) 
8. The Happy Hollisters at Circus Island  (1955) 
9. The Happy Hollisters and the Secret Fort  (1955) 
10. The Happy Hollisters and the Merry-Go-Round Mystery*  (1955) 
11. The Happy Hollisters at Pony Hill Farm*  (1956) 
12. The Happy Hollisters and the Old Clipper Ship  (1956) 
13. The Happy Hollisters at Lizard Cove  (1957) 
14. The Happy Hollisters and the Scarecrow Mystery  (1957) 
15. The Happy Hollisters and the Mystery of the Totem Faces  (1958) 
16. The Happy Hollisters and the Ice Carnival Mystery  (1958) 
17. The Happy Hollisters and the Mystery in Skyscraper City  (1959) 
18. The Happy Hollisters and the Mystery of the Little Mermaid  (1960) 
19. The Happy Hollisters and the Mystery at Missile Town  (1961) 
20. The Happy Hollisters and the Cowboy Mystery  (1961) 
21. The Happy Hollisters and the Haunted House Mystery  (1962) 
22. The Happy Hollisters and the Secret of the Lucky Coins  (1963) 
23. The Happy Hollisters and the Castle Rock Mystery  (1963) 
24. The Happy Hollisters and the Cuckoo Clock Mystery  (1963) 
25. The Happy Hollisters and the Swiss Echo Mystery  (1963) 
26. The Happy Hollisters and the Sea Turtle Mystery  (1964) 
27. The Happy Hollisters and the Punch and Judy Mystery  (1964) 
28. The Happy Hollisters and the Whistle Pig Mystery  (1964) 
29. The Happy Hollisters and the Ghost Horse Mystery  (1965) 
30. The Happy Hollisters and the Mystery of the Golden Witch  (1966) 
31. The Happy Hollisters and the Mystery of the Mexican Idol  (1967) 
32. The Happy Hollisters and the Monster Mystery  (1969) 
33. The Happy Hollisters and the Mystery of the Midnight Trolls  (1969) 

* Numbers 10 and 11 are sometimes switched in publication order, but Pony Hill Farm references their prior mystery about the Merry-Go-Round, so I'm listing Pony Hill Farm as #11.

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Louise Penny: Chief Inspector Armand Gamache

• Main character: Chief Inspector Armand Gamache of Sûreté du Québec, the provincial police force for Quebec
• Setting: Canada, mostly in and around the small Québécois town of Three Pines
• Bold type indicates a book I've read.

1. Still Life (2005)
2. A Fatal Grace (2006) 
3. The Cruelest Month (2007) 
4. A Rule Against Murder (2008) 
5. The Brutal Telling (2009)
6. Bury Your Dead (2010) 
7. A Trick of the Light (2011)
8. The Beautiful Mystery (2012) 
9. How the Light Gets In (2013) 
10. The Long Way Home (2014) 
11. The Nature of the Beast (2015) 
12. A Great Reckoning (2016)
13. Glass Houses (2017) 
14. Kingdom of the Blind (2018) 
15. A Better Man (2019)
16. All the Devils Are Here (2020)

In addition to the full-length novels, there has also been one novella (or long short story) issued:

1. The Hangman (2010)

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