Heading into Fall 1984, action shows were the second biggest genre after primetime soaps. Murder, She Wrote was finishing ahead of the big three action shows (The A-Team, Simon & Simon; Magnum, P.I.) from its first episode. 14 of Murder, She Wrote's first 22 episodes finished ahead of a new episode of at least one of the big three action shows. These episodes were
September 30, 1984: The Murder of Sherlock Holmes (series premiere), rating 18.9. Finished ahead of Magnum, P.I. (September 27: Echoes of the Mind (Part 1) (season 5 premiere), rating 18.4) and Simon & Simon (September 27: C'est Simon (season 4 premiere), rating 18.2).
October 7, 1984: Deadly Lady (episode 2), rating 20.3. Finished ahead of Magnum, P.I. (October 4: Echoes of the Mind (Part 2), rating 19.4).
November 25, 1984: Hit, Run and Homicide (episode 7), rating 19.7. Finished ahead of Simon & Simon (November 22: Almost Completely Out of Circulation, rating 19.5). Magnum, P.I. was a repeat on November 22.
December 9, 1984: We're Off to Kill the Wizard (episode 8 ), rating 22.3. Finished ahead of The A-Team (December 4: The Bells of St. Mary's, rating 21.4) and Magnum, P.I. (December 6 - Luther Gillis: File #001, rating 21.0).
January 13, 1985: Broadway Malady (episode 12), rating 21.8. Finished ahead of Magnum, P.I. (January 10: Professor Jonathan Higgins, rating 20.5). Simon & Simon was a repeat on January 10.
February 3, 1985: Murder to a Jazz Beat (episode 13), rating 22.0. Finished ahead of Magnum, P.I. (January 31: All for One (Part 1), rating 18.9).
February 10, 1985: My Johnny Lies Over the Ocean (episode 14), rating 19.9. Finished ahead of Magnum, P.I. (February 7: All for One (Part 2), rating 18.7).
February 17, 1985: Paint Me a Murder (episode 15), rating 20.5. Finished ahead of Magnum, P.I. (February 14: The Love-for-Sale Boat, rating 19.8).
February 24, 1985: Tough Guys Don't Die (episode 16), rating 21.7. Finished ahead of Magnum, P.I. (February 21: Let Me Hear the Music, rating 18.9). The A-Team was a repeat on February 19.
March 3, 1985: Sudden Death (episode 17), rating 21.6. Finished ahead of The A-Team (February 26: Knights of the Road, rating 19.3). Magnum, P.I. was a repeat on February 28.
March 10, 1985: Footnote to Murder (episode 18), rating 19.7. Finished ahead of Magnum, P.I. (March 7: Ms. Jones, rating 17.7). Simon & Simon was a repeat on March 7.
March 17, 1985: Murder Takes the Bus (episode 19), rating 22.4. Finished ahead of Magnum, P.I. (March 14: The Man from Marseilles, rating 15.8). No Simon & Simon on March 14. The A-Team was a repeat on March 12.
March 31, 1985: Armed Response (episode 20), rating 21.2. Finished ahead of Magnum, P.I. (March 28: Torah, Torah, Torah; rating 16.8). The A-Team was a repeat on March 26.
April 7, 1985: Murder at the Oasis (episode 21), rating 20.4. Finished ahead of Magnum, P.I. (April 4: A Pretty Good Dancing Chicken (season 5 finale), rating 19.4). Simon & Simon season 4 finale March 28.
On a win-loss basis, Murder, She Wrote's 1984/85 record vs. the action shows was
Magnum, P.I. 12-6
The A-Team 2-13
Simon & Simon 2-13
The tide shifted 1985/86 until the end of the action shows, as Murder, She Wrote began finishing ahead of all three of the action shows. The first Murder, She Wrote episode to finish ahead of a new episode of all three action shows was Joshua Peabody Died Here... Possibly (October 6, 1985, rating 23.5). This episode finished 4th for the week, behind The Cosby Show, Family Ties, and Dallas.
From 1985/86 until the end of the action shows, there was one episode of Murder, She Wrote that finished behind a new episode of one of the action shows. This episode was
May 1, 1988: Deadpan, rating 20.8. Finished behind Magnum, P.I. (May 1: Resolutions (series finale), rating 32.0). Simon & Simon season 7 finale April 7. The A-Team final episode March 8, 1987.
On a win-loss basis, Murder, She Wrote's overall records vs. the action shows were
Magnum, P.I. 50-7
Simon & Simon 51-13
The A-Team 26-13
I don't think anyone that watched the broadcast networks in 1984/85 expected this comforting drama to take down the big three action shows and big four primetime soaps from the beginning and then the following season become the highest rated drama across the broadcast networks, ahead of all the primetime soaps and action shows, and even ahead of the new hotness Miami Vice (or as Angela Lansbury referred to it in a 1985 Los Angeles Times interview, Miami Heat). In fact, new episodes of Miami Vice never finished ahead of new episodes of Murder, She Wrote. On a win-loss basis, Murder, She Wrote's overall record vs. Miami Vice was 76-0, a clean sweep.