Ravaged by the loss of Scooby-Doo in a snowmobiling accident, the Mystery Inc. gang must reunite one final time to plan the funeral and solve one last mystery.

Casey is attacked at random on the street and enlists in a local dojo led by a charismatic and mysterious Sensei in an effort to learn how to defend himself….

Spenser — an ex-cop better known for making trouble than solving it — just got out of prison and is leaving Boston for good. But first he gets roped into…