1 The Secret of the Old Clock 1930 1959
2 The Hidden Staircase 1930 1959
3 The Bungalow Mystery 1930 1960
4 The Mystery at Lilac Inn 1930 1961
5 The Secret Of Shadow Ranch 1931 1965
6 The Secret of Red Gate Farm 1931 1961
7 The Clue in the Diary 1932 1962
8 Nancy's Mysterious Letter 1932 1968
9 The Sign of the Twisted Candles 1933 1968
10 The Password to Larkspur Lane 1933 1966
11 The Clue of the Broken Locket 1934 1965
12 The Message in the Hollow Oak 1935 1972
13 The Mystery of the Ivory Charm 1936 1974
14 The Whispering Statue 1937 1970
15 The Haunted Bridge 1937 1972
16 The Clue of the Tapping Heels 1939 1969
17 The Mystery of the Brass-Bound Trunk 1940 1976
18 The Mystery at the Moss-Covered Mansion 1941 1971
19 The Quest of the Missing Map 1942 1969
20 The Clue in the Jewel Box 1943 1972
21 The Secret in the Old Attic 1944 1970
22 The Clue in the Crumbling Wall 1945 1973
23 The Mystery of the Tolling Bell 1946 1973
24 The Clue in the Old Album 1947 1977
25 The Ghost of Blackwood Hall 1948 1967
26 The Clue of the Leaning Chimney 1949 1967
27 The Secret of the Wooden Lady 1950 1967
28 The Clue of the Black Keys 1951 1968
29 The Mystery at the Ski Jump 1952 1968
30 The Clue of the Velvet Mask 1953 1969
31 The Ringmaster's Secret 1953 1974
32 The Scarlet Slipper Mystery 1954 1974
33 The Witch Tree Symbol 1955 1975
34 The Hidden Window Mystery 1956 1975
35 The Haunted Showboat 1957
36 The Secret of the Golden Pavilion 1959
37 The Clue in the Old Stagecoach 1960