Part 1 Explosion in Berwyn Mountains North Wales and subsequent sighting of craft in the village of LLandrillo - to read more about this strange incident check out the following LINK
Apparent Scientific Explanation for the incident seems to make this 'case closed'
Part 3 Further investigation of the Berwyn incident by Jenny Randell after an interview with Nurse Pat Evans in 1980's resurrected this a a UFO incident. The documentary continues with the sightings in Pen-Y-Bryn by Gamekeeper Geraint Edwards on Feb 15th 1974. Sharon Rowlands finds out the hard way what happens when you make a UFO encounter public, after her sighting and video footage during October 2000 in Bonsall Derbyshire.
Part 4 The men in black with a twist
For interesting sightings in North Wales check out this amazing BBC site by following this LINK