Portwenn has a new police officer following the departure of PC Mark Mylow after his doomed marriage. His replacement is PC Joseph Penhale, who appears to have an odd affliction which causes him to fall asleep suddenly at strange times. The doctor discovers that he has narcolepsy brought on by a kick to the head from a horse suffered two years earlier. Village plumber Bert Large is having a midlife crisis. His son Al has left the village on his travels round the world and Bert feels left out in the cold. Doc Martin offers no help.