 The serial was the fourteenth of the sixty-six serials produced by the studio.An escaped criminal, known as Harry Crowl, but preferring to be called by his prison number "39013" (pronounced Thirty Nine - Oh - Thirteen), seeks revenge on the man who sent him to prison, millionaire philanthropist Horace Granville.He kidnaps Granville, imprisoning him within his own house, and disguises himself to take Granville's place, as the frail old man in a clean room, necessary for his health, with the only other person allowed past the glass barrier being his doctor.