"Better Call Saul": S'all done

Bob Odenkirk as Gene in "Better Call Saul" (Greg Lewis/AMC/Sony Pictures Television)

The following contains spoilers for the "Better Call Saul" series finale, "Saul Gone."

If regret is a time machine, guilt is the key that starts the engine. This is the last lesson "Better Call Saul" leaves us with through the stations of Jimmy McGill's acts of penance in "Saul Gone," starting with disposing of Gene Takavic in a filthy dumpster.