Lt. Frank Ballinger is a no-nonsense plain clothes cop in the elite M Squad Division. The Squad's task is to root out organised crime and corruption in America's Second City, Chicago.
| Title | Air Date | Duration | ||
|---|---|---|---|---|
| Season 1 | Episode 1 | The Golden Look | 1957-09-20 | 30 min |
| Season 1 | Episode 2 | Watchdog | 1957-09-27 | 30 min |
| Season 1 | Episode 3 | Neighborhood Killer | 1957-10-04 | 30 min |
| Season 1 | Episode 4 | Pete Loves Mary | 1957-10-11 | 30 min |
| Season 1 | Episode 5 | Face of Evil | 1957-10-18 | 30 min |
| Season 1 | Episode 6 | Street of Fear | 1957-11-01 | 30 min |
| Season 1 | Episode 7 | The Matinee Trade | 1957-11-08 | 30 min |
| Season 1 | Episode 8 | The Hard Case | 1957-11-15 | 30 min |
| Season 1 | Episode 9 | Killer in Town | 1957-11-22 | 30 min |
| Season 1 | Episode 10 | Diamond Hard | 1957-11-29 | 30 min |
| Season 1 | Episode 11 | The Alibi Witness | 1957-12-06 | 30 min |
| Season 1 | Episode 12 | The Specialists | 1957-12-13 | 30 min |
| Season 1 | Episode 13 | Family Portrait | 1957-12-20 | 30 min |
| Season 1 | Episode 14 | The Palace Guard | 1957-12-27 | 30 min |
| Season 1 | Episode 15 | The Slow Trap | 1958-01-03 | 30 min |
| Season 1 | Episode 16 | The Cover Up | 1958-01-10 | 30 min |
| Season 1 | Episode 17 | Blue Indigo | 1958-01-17 | 30 min |
| Season 1 | Episode 18 | The Long Ride | 1958-01-24 | 30 min |
| Season 1 | Episode 19 | Shakedown | 1958-01-31 | 30 min |
| Season 1 | Episode 20 | Dolly's Bear | 1958-02-07 | 30 min |
| Season 1 | Episode 21 | Lover's Lane Killing | 1958-02-14 | 30 min |
| Season 1 | Episode 22 | The Frightened Wife | 1958-02-21 | 30 min |
| Season 1 | Episode 23 | The Black Mermaid | 1958-02-28 | 30 min |
| Season 1 | Episode 24 | The Man in Hiding | 1958-03-07 | 30 min |
| Season 1 | Episode 25 | Chicago Bluebeard | 1958-03-14 | 30 min |
| Season 1 | Episode 26 | Girl Lost | 1958-03-21 | 30 min |
| Season 1 | Episode 27 | Hideout | 1958-03-28 | 30 min |
| Season 1 | Episode 28 | Shot in the Dark | 1958-04-04 | 30 min |
| Season 1 | Episode 29 | The Twenty-Six Girl | 1958-04-11 | 30 min |
| Season 1 | Episode 30 | Fight | 1958-04-18 | 30 min |
| Season 1 | Episode 31 | Guilty Alibi | 1958-04-25 | 30 min |
| Season 1 | Episode 32 | The Healer | 1958-05-02 | 30 min |
| Season 1 | Episode 33 | Day of Terror | 1958-05-09 | 30 min |
| Season 1 | Episode 34 | The $20 Plates | 1958-05-16 | 30 min |
| Season 1 | Episode 35 | The Double Face | 1958-05-23 | 30 min |
| Season 1 | Episode 36 | The System | 1958-05-30 | 30 min |
| Season 1 | Episode 37 | Woman from Paris | 1958-06-06 | 30 min |
| Season 1 | Episode 38 | Accusation | 1958-06-13 | 30 min |
| Season 2 | Episode 1 | More Deadly | 1958-09-19 | 30 min |
| Season 2 | Episode 2 | Dead or Alive | 1958-09-26 | 30 min |
| Season 2 | Episode 3 | The Missing Claimant | 1958-10-03 | 30 min |
| Season 2 | Episode 4 | The Refugee | 1958-10-10 | 30 min |
| Season 2 | Episode 5 | The Trap | 1958-10-24 | 30 min |
| Season 2 | Episode 6 | Force of Habit | 1958-10-31 | 30 min |
| Season 2 | Episode 7 | The Phantom Raiders | 1958-11-07 | 30 min |
| Season 2 | Episode 8 | The Merits of the Case | 1958-11-14 | 30 min |
| Season 2 | Episode 9 | The Big Kill | 1958-11-21 | 30 min |
| Season 2 | Episode 10 | The Sitters | 1958-11-28 | 30 min |
| Season 2 | Episode 11 | The Executioner | 1958-12-05 | 30 min |
| Season 2 | Episode 12 | The Widows | 1958-12-12 | 30 min |
| Season 2 | Episode 13 | Contraband | 1958-12-19 | 30 min |
| Season 2 | Episode 14 | Prescription for Murder | 1958-12-26 | 30 min |
| Season 2 | Episode 15 | The Teacher (aka Trade School) | 1959-01-02 | 30 min |
| Season 2 | Episode 16 | The Third Shadow | 1959-01-09 | 30 min |
| Season 2 | Episode 17 | One Man's Life | 1959-01-23 | 30 min |
| Season 2 | Episode 18 | The Jumper | 1959-01-30 | 30 min |
| Season 2 | Episode 19 | The Last Act | 1959-02-06 | 30 min |
| Season 2 | Episode 20 | Mugger Murder | 1959-02-13 | 30 min |
| Season 2 | Episode 21 | The Star Witness | 1959-02-20 | 30 min |
| Season 2 | Episode 22 | The Take Over | 1959-02-27 | 30 min |
| Season 2 | Episode 23 | Voluntary Surrender | 1959-03-06 | 30 min |
| Season 2 | Episode 24 | Death Threat | 1959-03-13 | 30 min |
| Season 2 | Episode 25 | The Harpies | 1959-03-20 | 30 min |
| Season 2 | Episode 26 | Ghost Town | 1959-03-27 | 30 min |
| Season 2 | Episode 27 | The Vanishing Lady | 1959-04-03 | 30 min |
| Season 2 | Episode 28 | The Crush Out | 1959-04-10 | 30 min |
| Season 2 | Episode 29 | The Fire Makers | 1959-04-17 | 30 min |
| Season 2 | Episode 30 | The Terror on Dark Street | 1959-04-24 | 30 min |
| Season 2 | Episode 31 | Robber's Roost | 1959-05-01 | 30 min |
| Season 2 | Episode 32 | The Baited Hook | 1959-05-08 | 30 min |
| Season 2 | Episode 33 | Model in the Lake | 1959-05-15 | 30 min |
| Season 2 | Episode 34 | The Outsider | 1959-05-22 | 30 min |
| Season 2 | Episode 35 | High School Bride | 1959-05-29 | 30 min |
| Season 2 | Episode 36 | The Dangerous Game | 1959-06-05 | 30 min |
| Season 2 | Episode 37 | Decoy in White | 1959-06-12 | 30 min |
| Season 2 | Episode 38 | Mr. Grim's Rabbits | 1959-06-19 | 30 min |
| Season 2 | Episode 39 | Platter Pirates | 1959-06-26 | 30 min |
| Season 2 | Episode 40 | Death Is a Clock | 1959-07-03 | 30 min |
| Season 3 | Episode 1 | Ten Minutes to Doomsday | 1959-09-18 | 30 min |
| Season 3 | Episode 2 | The European Plan | 1959-09-25 | 30 min |
| Season 3 | Episode 3 | Sunday Punch | 1959-10-02 | 30 min |
| Season 3 | Episode 4 | Jeopardy by Fire | 1959-10-09 | 30 min |
| Season 3 | Episode 5 | Murder in C-Sharp Minor | 1959-10-16 | 30 min |
| Season 3 | Episode 6 | The Human Bond | 1959-10-23 | 30 min |
| Season 3 | Episode 7 | Mama's Boy | 1959-10-30 | 30 min |
| Season 3 | Episode 8 | Shred of Doubt | 1959-11-06 | 30 min |
| Season 3 | Episode 9 | Death by Adoption | 1959-11-20 | 30 min |
| Season 3 | Episode 10 | Another Face, Another Life | 1959-11-27 | 30 min |
| Season 3 | Episode 11 | Voice from the Grave | 1959-12-04 | 30 min |
| Season 3 | Episode 12 | The Upset | 1959-12-11 | 30 min |
| Season 3 | Episode 13 | One of Our Armored Cars Is Missing | 1959-12-18 | 30 min |
| Season 3 | Episode 14 | The Ivy League Bank Robbers | 1959-12-25 | 30 min |
| Season 3 | Episode 15 | The Twisted Way | 1960-01-01 | 30 min |
| Season 3 | Episode 16 | The Man Who Went Straight | 1960-01-08 | 30 min |
| Season 3 | Episode 17 | The Second Best Killer | 1960-01-15 | 30 min |
| Season 3 | Episode 18 | Pitched Battle at Bluebell Acres | 1960-01-22 | 30 min |
| Season 3 | Episode 19 | The Man Who Lost His Brain | 1960-01-26 | 30 min |
| Season 3 | Episode 20 | Debt of Honor | 1960-02-02 | 30 min |
| Season 3 | Episode 21 | The Man with Frank's Face | 1960-02-09 | 30 min |
| Season 3 | Episode 22 | Burglar's Nightmare | 1960-02-16 | 30 min |
| Season 3 | Episode 23 | Needle in the Haystack | 1960-02-23 | 30 min |
| Season 3 | Episode 24 | Race to Death | 1960-03-01 | 30 min |
| Season 3 | Episode 25 | The Velvet Stake-out | 1960-03-08 | 30 min |
| Season 3 | Episode 26 | Anything for Joe | 1960-03-15 | 30 min |
| Season 3 | Episode 27 | A Kid Up There | 1960-03-22 | 30 min |
| Season 3 | Episode 28 | Diary of a Bomber | 1960-03-29 | 30 min |
| Season 3 | Episode 29 | Let There Be Light | 1960-04-05 | 30 min |
| Season 3 | Episode 30 | A Gun for Mother's Day | 1960-04-12 | 30 min |
| Season 3 | Episode 31 | The Man with the Ice | 1960-04-19 | 30 min |
| Season 3 | Episode 32 | Dead Parrots Don't Talk | 1960-05-03 | 30 min |
| Season 3 | Episode 33 | Grenade for a Summer Evening | 1960-05-10 | 30 min |
| Season 3 | Episode 34 | Two Days for Willy | 1960-05-17 | 30 min |
| Season 3 | Episode 35 | Badge for a Coward | 1960-05-24 | 30 min |
| Season 3 | Episode 36 | Closed Season | 1960-05-31 | 30 min |
| Season 3 | Episode 37 | Fire in the Sky | 1960-06-07 | 30 min |
| Season 3 | Episode 38 | The Tiger's Cage | 1960-06-14 | 30 min |
| Season 3 | Episode 39 | The Bad Apple | 1960-06-21 | 30 min |
| Production | Maxwell Shane | Producer |
