The truth is, we all watched (and still watch) Murder She Wrote to see the wonderful Angela Lansbury, after a long career where she was supporting cast more often than leading lady. So Jessica Fletcher became a career defining role, and one which suited her perfectly.
To be honest, the puzzle value of the mysteries wasn't that high, and certainly not meant to be, as the writers didn't want to confuse and baffle the average viewer. More often than not, the solution came through "guilty knowledge", so you had to pay attention to throw-away lines to catch them. I had a different method. More often than not, the actor who seems to have no better reason for appearing is the guilty party.
That brings us to my complaint about this episode. There was no defining clue. The culprit is merely presented and the motive suddenly explained in dialogue.
However, this episode always intrigued not only me, but most MSW fans, as to my knowledge it's the only one to bring back a past murderer, and what a great choice to make for that ... Jessica's charming first publisher from the two-hour premier/pilot!
It makes for a fascinating show as he tries to prove his remorse and his dedication to honesty.