Dan Abnett in the first story immediately instills curiosity. The nature of the mystery requires people turning into statues of stone. Given the Scooby formula that always there is a rational explanation for seeming supernatural events, how on earth can science explain instantaneous petrification? Mr. Abnett comes up with a delightful solution that still plays fair with the reader.
...Characterization can be overlooked in any mystery to favor the plot, but both authors and artists keep Mystery Inc. in near perfect pitch. The camaraderie between them feels comfortable and genuine, and because of this attention to interaction, the reader cares about what happens on the cover: Daphne and Fred turned into statues.