This poem is from the Doctor Who story Full Circle by Andrew Smith

 When Mistfall comes
  The sun is swallowed whole
 By sky-borne darkness
  The world turns to cold
 
 When Mistfall comes
  The globe transforms its face
 Grey fog clouds probes
  They reach to every place

 When Mistfall comes
  The planet that has slept
 Awakes, unleashing terror
  Bringing death if you forget

                         First Decider Yanek Pitrus
                           Tenth generation starliner


'Doctor Who' series copyright (C) British Broadcasting Corperation 1986