| The Case of the Missing Doll (Pt. 4) | 405 | 1940-05-09 | |
| The Case of the Woman Who Wasn't Needed (Pt. 1) | 414 | 1940-05-30 | |
| TCOT Woman Who Wasn't Needed - [3-3] | 416 | 1940-06-05 | [G Plot] The last episode of the story. |
| The Case of the Young Husband Who Thought His Wife Failed Him (Pt. 1) | 552 | 1941-04-17 | |
| TCOT Moonless Night | 966 | 1944-01-06 | [G Plot] Mr. Keen's in the deep South to find a missing southern gentleman on a plantation with black walnut trees. |
| TCOT Missing Witness | 967 | 1944-01-13 | [G Plot] A famous fashion designer has killed her daughter's lover. . . or has she? |
| TCOT Girl Who Sang Too Well | 968 | 1944-01-20 | [G Plot] Murder plays the Palladium as big time vaudeville leads to a star performer's disappearance. |
| TCOT Girl Who Flirted | 970 | 1944-02-03 | [G Plot] A murderer in an Egyptian tomb leads to a kidnapped girl and a stolen painting. |
| TCOT Boy Who Used Big Words | 971 | 1944-02-10 | [G Plot] A twelve year old with an extraordinary vocabulary is kidnapped after his mysterious Uncle Bill is killed. |
| TCO Mr Trevor's Secret | 972 | 1944-02-17 | |
| TCO Murder in the Air | 973 | 1944-02-24 | [G Plot] A woman found hiding in Mr. Keen's closet is the target of three murder attempts. |
| TCOT Strange Display | 976 | 1944-03-16 | [G Plot] Murder takes place in a department store, but Mr. |
| TCOT Leaping Dog | 980 | 1944-04-13 | [G Plot] Aerowax. |
| TCOT Woman in Blue | 989 | 1944-06-15 | [G Plot] Black Flag. |
| TCOT Frightened Child | 1012 | 1944-11-16 | [G Plot] A five year old boy has been left to die in a dark, abandoned warehouse. |
| The Nightmare Murder Case | 1016 | 1944-12-14 | [G Plot] A woman spends her husband's savings on secret voice lessons for her daughter. |
| TCOT Absent Minded Professor | 1029 | 1945-03-15 | [G Plot] The wife of a quiet poetry professor dies, then his housekeeper, then his daughter. |
| The Strange Case of Charlie Lorimer | 1066 | 1945-11-29 | |
| TCOT Glamorous Widow | 1091 | 1946-05-23 | [G Plot] Which one of her four boyfriends did her in? Bennett Kilpack, Frank Hummert (producer), Anne Hummert (producer), Larry Elliott (announcer). |
| The Identical Twins Murder Case (Partial) | 1210 | 1948-10-28 | |
| TCO Murder and the Star of Death | 1242 | 1949-06-09 | [G Plot] A magnificent jewel is stolen; a killer strikes in the dark. |
| TCO Murder and the Bloodstained Necklace | 1256 | 1949-09-15 | [G Plot] A widow for one week is found dead in a hotel room with a string of worthless pearls clutched in her hand. |
| The Yellow Talon Murder Case | 1257 | 1949-09-22 | [G Plot] Murder stalks a large estate along the Hudson River, fifty miles north of the city (Croton?). The killer is apparently a bird of enormous size. |
| TCO Murder With a Thousand Witnesses | 1258 | 1949-09-29 | [G Plot] A kindly county squire is poisoned while judging a baking contest at a county fair. |
| TCOT Man Who Invented Death | 1259 | 1949-10-06 | [G Plot] A modern alchemist has been electrocuted to learn his secrets. |
| The Silver Dagger Murder Case | 1260 | 1949-10-13 | [G Plot] A young woman, about to break off with a young playwright, is knifed. |
| TCOT Ruthless Murderers | 1262 | 1949-10-27 | [G Plot] A man just out of prison after five years had sworn to kill Mr. |
| The Forgotten Cave Murder | 1263 | 1949-11-03 | [G Plot] Two men in a search of hidden gold find death instead. |
| The Engaged Girl Murder Case | 1264 | 1949-11-10 | [G Plot] Mr. Keen solves a murder case while on horseback! Frank Hummert (producer), Anne Hummert (producer), Larry Elliott (announcer), Bennett Kilpack, Lawrence Klee (dialogue). |
| TCOT Rushville Murder | 1272 | 1950-01-05 | [G Plot] A madwoman has escaped from the asylum and committed murder, but what about her sane sister? Frank Hummert (originator, producer), Anne Hummert (originator, producer), Bennett Kilpack, Lawrence Klee (writer), Larry Elliott (announcer). |
| The Bride and Groom Murder Case (AFRS) | 1274 | 1950-01-19 | [G Plot] A bride of only a few days is pushed off a fourteen story roof. It later is discovered she was a millionaire. |
| The Telephone Book Murder Case | 1275 | 1950-01-26 | [G Plot] A wealthy oil man, about to be married, is murdered. Believe it or not. . . it looks like the butler did it! |
| TCO Murder and the Jewel Thief | 1277 | 1950-02-09 | [G Plot] Kansas Karl,' a notorious jewel thief, decides to go straight. |
| TCOT Two Faced Murderer | 1278 | 1950-02-16 | [G Plot] A mask provides the clue to a killer with two faces! Frank Hummert (originator, producer), Anne Hummert (originator, producer), Lawrence Klee (dialogue), Bennett Kilpack, Dick Dunham (announcer). |
| The Tea Leaf Murder Case | 1279 | 1950-02-23 | |
| TCOT Melody of Murder | 1281 | 1950-03-09 | [G Plot] Who is the Antwerp Strangler? The key to the crime is in a pianist's hands! Frank Hummert (originator, producer), Anne Hummert (originator, producer), Lawrence Klee (dialogue), Bennett Kilpack, Larry Elliott (announcer). |
| The Innocent Flirtation Murder Case | 1282 | 1950-03-16 | [G Plot] A modern duel leads to a murder and an attempted frame. |
| TCOT Murdered Detective | 1285 | 1950-04-06 | [G Plot] A private eye is knifed in a phone booth and the trail leads to stolen charity funds. |
| The Eccentric Millionaire Murder Case | 1286 | 1950-04-13 | |
| The Country Club Murder Case | 1287 | 1950-04-20 | [G Plot] A strangulation at a exclusive Westchester Club leads to forgery as well. |
| TCOT Woman Who Married a Murderer | 1288 | 1950-04-27 | |
| The King Cobra Murder Case | 1289 | 1950-05-04 | [G Plot] A snake is used to kill on an ocean liner. |
| TCO Murder and the Missing Car | 1290 | 1950-05-11 | [G Plot] A body is found in a car trunk. |
| The Broken Window Murder Case | 1292 | 1950-05-25 | [G Plot] A dead rabbit provides Mr. Keen with the final clue to a killer. |
| The Quicksand Murder Case | 1293 | 1950-06-01 | [G Plot] A real estate agent losses his new tenant. . . to a murderess. |
| The Skull and Crossbones Murder Case | 1295 | 1950-06-15 | Lemuel Barker is poisoned one evening in his home of 5th Avenue. His widow Audrey asks Mr. Keen to help find his murderer. The two prime suspects are Emily Cross, who has been Mr. Barker's housekeeper for years and hoped he would some day ask her to marry him, and Barker's nephew Peter Hunt, who stole $5,000 from him and had not yet returned it at the time of his death. But Mr. Keen and his friend Mike Clancy, a former police inspector, cannot rule out Audrey Barker. She 'finds' the bottle that contained the poison. Also of interest is Ted Garrett, Barker's former private secretary, who becomes involved when Emily Cross turns to him for help. |
| The Skull and Crossbones Murder Case | 1295 | 1950-06-15 | Lemuel Barker is poisoned one evening in his home of 5th Avenue. His widow Audrey asks Mr. Keen to help find his murderer. The two prime suspects are Emily Cross, who has been Mr. Barker's housekeeper for years and hoped he would some day ask her to marry him, and Barker's nephew Peter Hunt, who stole $5,000 from him and had not yet returned it at the time of his death. But Mr. Keen and his friend Mike Clancy, a former police inspector, cannot rule out Audrey Barker. She 'finds' the bottle that contained the poison. Also of interest is Ted Garrett, Barker's former private secretary, who becomes involved when Emily Cross turns to him for help. |
| The Airport Murder Case | 1335 | 1951-03-22 | |
| TCO Murder and the Strange Woman | 1352 | 1951-07-20 | [G Plot] A popular crooner is killed while rehearsing. Was it done by the madwoman locked in his dressing room? |
| The Photograph Album Murder Case | 1353 | 1951-07-27 | [G Plot] An impoverished actress, taken into a wealthy society home, is found murdered outside the door. |
| The Strange Murder of Carrie Ellis | 1354 | 1951-08-03 | [G Plot] Mr. Keen has discovered the identity of a murderer, but is unable to do anything about it. |
| The Abandoned Well Murder Case | 1355 | 1951-08-10 | [G Plot] A wealthy old man has been shot and thrown down as well. . whodunit? |
| The Poisoned Sandwich Murder Case | 1356 | 1951-08-17 | [G Plot] A law student telephones Mr. Keen for protection, but dies while on the phone. |
| TCO Murder at a Mile a Minute | 1372 | 1951-12-06 | [G Plot] A man is shot while driving through the park. |
| The Silver Candlestick Murder Case | 1386 | 1952-03-13 | [G Plot] A photographer's model is killed and his body stuffed in the coal bin. |
| The Rented Cottage Murder Case | 1389 | 1952-04-03 | [G Plot] A strange cottage, renting for $25 during the housing shortage, is the scene of the murder of a cripple. The clue is in the crutches. |
| The Mother's Plea Murder Case | 1390 | 1952-04-10 | |
| The Gossip Column Murder Case | 1418 | 1952-10-24 | |
| The Case of Murder and the Prize-Winning Bull | 1420 | 1952-11-07 | |
| The Shrieking Prisoner Murder Case [1-4 - 15mins] | 1505 | 1954-06-21 | [G Plot] The strange Carson sisters block Mr. Keen's investigation of the murder of Donald Travers. |
| The Shrieking Prisoner Murder Case [2-4 - 15mins] | 1506 | 1954-06-23 | [G Plot] Insane Amy Carson is kept imprisoned in the strange house. George implicates ax-wielding Luther Prague. |
| The Shrieking Prisoner Murder Case [3-4 - 15mins] | 1507 | 1954-06-24 | [G Plot] A $50 bill and the dead man's wallet give Mr. Keen clues as he meets the madwoman. |
| The Shrieking Prisoner Murder Case [4-4 - 15mins] | 1509 | 1954-06-25 | [G Plot] The conclusion of the story, the killer is revealed. |
| TCO Murder and the Revengeful Ghost | 1662 | 1955-02-22 | |
