This is an uncharacteristic Bus Stop episode. A strange tale of guilt and a fiancées possessiveness that seems to reach from beyond the grave.
As we watch Joe Elliot appear to slip further and further from reality, we begin to wonder if he's not right about the shadowy visits from Donna. We see him walk into her shadow as her brother (and later the DA) looks on. The shocked look on their faces would indicate they see it too, but this is not made entirely clear. Perhaps they are only shocked by Joe's behavior. Different viewers will probably have different interpretations of what happened in the story. This must've been somewhat experimental at the time. Director John Newland (One Step Beyond) lets the story drift into a netherworld like feel. The scenes where Joe "sees" Donna will have the ability to raise goosebumps on some viewers. It plays with our imagination in a similar way to the 1963 movie "The Haunting" Definitely a top notch way to cap this series.
Watch it with the lights out!