The Gorgon is a quiet film in comparison to the rest of the Hammer Horror canon. It feels a bit like they ran out of monsters from the Universal collection and were reaching for some new things to exploit. Unfortunately the Gorgon is not exactly terrifying as the legends suggest and looks a bit like someone in curlers.
Even so, it is always a pleasure to watch Cushing and Lee and as a bonus we have Barbara Shelley of my favorite Quatermass and the Pit and Patrick Troughton (the second Doctor Who) as the local police captain.
Worth watching for Hammer completists but not essential for the casual fan.