• Season 4 - Episode 23 : Runaway Mar 18, 1976

    Stone and a 15-year-old runaway girl search for the same man, her fugitive father; guest Billy Green Bush.

  • Season 4 - Episode 22 : Alien Country Mar 11, 1976

    An illegal alien is wanted for murder; Stone and Keller search for the real killer; guest A Martinez.

  • Season 4 - Episode 21 : Superstar Mar 4, 1976

    Stone and Keller clash with a visiting New York police officer (Paul Sorvino) while trying to capture a killer.

  • Season 4 - Episode 20 : Clown of Death Feb 26, 1976

    Stone and Keller investigate three murders among circus personnel; guests Lynne Marta, David Birney, Dick Van Patten.

  • Season 4 - Episode 19 : Judgement Day Feb 19, 1976

    Stone and Keller intercept the murderer of five lawyers who plans to kill another; guest Lynette Mettey.

  • Season 4 - Episode 18 : Underground Jan 29, 1976

    A police officer signs a fake resignation and goes under cover to expose a huge gambling operation; guest Jason Evers.

  • Season 4 - Episode 17 : Requiem for a Murder Jan 22, 1976

    A bishop (Richard Basehart) is fatally shot while kneeling in prayer; guests Fionnula Flanagan, William Windom.

  • Season 4 - Episode 16 : The Honorable Profession Jan 15, 1976

    The star witness in a robbery that resulted in a police officer's death vanishes; guests Robert Reed, Larry Manetti.

  • Season 4 - Episode 15 : Police Buff Jan 8, 1976

    A man on trial for a police officer's murder is freed, then slain by a vigilante; guests Bill Bixby, Christopher Stone.

  • Season 4 - Episode 14 : Most Likely to Succeed Dec 18, 1975

    Robbery seems to be the motive for a teacher's death, until a student is nearly killed; guest Kristoffer Tabori.

  • Season 4 - Episode 13 : Spooks for Sale Dec 11, 1975

    When Stone and Keller are called in to solve the mystery of a bugged factory, they learn that the owner has a long record of criminal involvement.

  • Season 4 - Episode 12 : The Cat's Paw Dec 4, 1975

    Tensions develop as Stone and another inspector pursue different theories on how to solve the case of a cat burglar who is also a killer.

  • Season 4 - Episode 11 : Merchants of Death Nov 20, 1975

    Rival street gangs go to war after a member is murdered; guests Greg Morris, Lonny Chapman.

  • Season 4 - Episode 10 : Dead Air Nov 13, 1975

    A radio personality is charged with slaying a girl who attempted to blackmail him; guests Larry Hagman, Ina Balin.

  • Season 4 - Episode 9 : Web of Lies Nov 6, 1975

    Details surrounding a diamond robbery and a police officer's death become confused; guests Pat Hingle, Robert Walden.

  • Season 4 - Episode 8 : Trail of Terror Oct 30, 1975

    Killers chase Keller while he is transporting a prisoner; guests Meg Foster, Greg Mullavey, James Woods.

  • Season 4 - Episode 7 : Murder by Proxy Oct 23, 1975

    Stone and Keller look into violence and murder in a neighborhood; guests Bradford Dillman, Sorrell Booke, John Ritter.

  • Season 4 - Episode 6 : Deadly Silence Oct 16, 1975

    Injured Stone must undergo delicate surgery to restore his hearing; guests Meredith Baxter, Gerald McRaney.

  • Season 4 - Episode 5 : School of Fear Oct 9, 1975

    A deranged teacher takes Keller hostage during a student-abduction investigation; guest Maurice Evans.

  • Season 4 - Episode 4 : Men Will Die Oct 2, 1975

    When a distraught rape victim shoots and kills one of her attackers, she finds herself charged with first-degree murder.

  • Season 4 - Episode 3 : No Place to Hide Sep 25, 1975

    A prison gang pressures a convict and his wife into smuggling drugs; guests Stefanie Powers, Ji-Tu Cumbuka.

  • Season 4 - Episode 2 : The Glass Dart Board Sep 18, 1975

    The efficiency of Stone's new superior hampers efforts to catch a psychotic killer; guest Patrick O'Neal.

  • Season 4 - Episode 1 : Poisoned Snow Sep 11, 1975

    Personal tragedy leads a narcotics officer to seek retribution; guests Clu Gulager, Mark Hamill, Anthony Geary.