After decades in the business, Jennifer Copping is the kind of actress known to audiences from a long list of titles rather than from one. The bulk of the career has been spent in horror. The count stands at 44 titles, and the range inside it is wide. The role of Margaret in 'Slither' is the one that keeps being brought up. The list also holds 'Barbie in the 12 Dancing Princesses'. The career opened quietly, the way most long ones do.