A strange new virus has appeared, which only attacks strains of grasses such as wheat and rice, and the world is descending into famine and chaos. Architect John, along with his family and friends, is making his way from London to his brother's farm in northern England where there will hopefully be food and safety for all of them.

Nigel Davenport
as John Custance

Jean Wallace
as Ann Custance

John Hamill
as Roger Burnham

Lynne Frederick
as Mary Custance

Patrick Holt
as David Custance

Ruth Kettlewell
as Fat Woman

M.J. Mathews
as George

Michael Percival
as Police Constable

Tex Fuller
as Mr. Beaseley

Simon Merrick
as T.V. Interviewer