Investigative reporter Terry Scanlon follows up the strange goings on in Llanfairfach, with interviews with people there at the time, including Professor Clifford Jones and mysterious boss, Stevens.
| Actor | Role |
|---|---|
 Mark GatissTerry Scanlon | Terry Scanlon |
 Tony AdamsMark Elgin | Mark Elgin |
 Stewart BevanProfessor Clifford Jones | Professor Clifford Jones |
| RRoy EvansTalfryn Pritchard | Talfryn Pritchard |
 Ian HallardGary Talbot | Gary Talbot |
| JJulia DalkinJanet | Janet |
 Jonathan RigbySir Alec Douglas-Hodge | Sir Alec Douglas-Hodge |
| DDavid Rees TalbotEvan Evans | Evan Evans |
 Alexander KirkHopkins the Security | Hopkins the Security |
 Jerome WillisJocelyn Stevens | Jocelyn Stevens |
 John DearthBOSS (voice) (archive footage) | BOSS (voice) (archive footage) |