First broadcast 12th/13th September 2004.
Tensions are running high in the 'leaderless' team as Leo and Harry clash over an investigation into an outbreak of breathing difficulties among children on the South Coast.
Alex Hughes - Teacher
Rebecca Bridges - Lanny Forbes
Billy Hill - Paul Williams
Sam Friend - Pat
William Gaminara - Leo Dalton
Tom Ward - Dr. Harry Cunningham
Graham O'Mara - Man on Slab
Kate Fleetwood - Sienna Ricci
Emma Handy - DS Gwenda Newton
Tom Wu - Dr. Yip
Philip Bird - DCI Jim Tennant
Peter Wight - Lucas Garner
Ozzie Yue - Micky Choo
Phyllis Logan - Helen Wharton
Anton Lesser - Marcus Gwilym
Ian Peck - Daryl Butler
David Harewood - Angus Stuart
Natalie Press - Nicola Butler (as Nathalie Press)
Amymay Bowes - Nurse
John Byrne - Boat Yard Worker
James Tucker - Man in Cafe
