Annabelle Apsion

The team is busy at work when an alarm goes off. Everyone groans - it's an EERIE (Extreme Emergency Response Initiative Exercise). They must act exactly as if there's a national emergency - in this case, germ warfare in Central London. As the exercise goes ahead, information dries up, power and phone lines go down, victims try to break into Thames House - and suddenly Harry gets sick. The team tries to stay calm, but doubts start to set in, is this actually for real?

Louisa and James have an awkward final goodbye with Martin after she decides to leave the doctor. But when Martin notices something on her brain scan, he must rush to save her. Meanwhile, Bert and Jennifer’s engagement party is interrupted when tragedy strikes.

PC Penhale spreads pandemonium throughout the village, and Bert pops the question to Jennifer.

Martin and Louisa are woken up by two fisherman after the discovery of a collapsed mystery man. Unfortunately Martin faces scrutiny after he helps the stranger. Meanwhile, Louisa has a hard time trusting James’ new sitter and finds herself sneaking around to check up on the man.

Mrs Tishell returns to the village. Martin has to work out what is wrong with beach comber Lorna. Al and Morwenna have an internet dating disaster, and romance is blossoming for Bert and Jennifer.