PC Mark Mylow can't persuade Dr Ellingham to be his best man, but Al Large agrees. The stag weekend – a camping trip – goes wrong when an adder bites Mark’s ankle and he suffers a potentially fatal allergic reaction. Meanwhile, Dr Ellingham deals with a spate of weever fish stings among teenage boys playing a dangerous game of dare.
Elenco: Martin Clunes , Caroline Catz , Joe Absolom , Ian McNeice , Selina Cadell , Katherine Parkinson , Stephanie Cole , Angeline Ball , Roger Lloyd Pack , Jake Wood , Lia Williams , Stewart Wright , Chris O'Dowd , Amanda Abbington , Lucy Punch , Eileen Atkins , John Marquez , Jessica Ransom , Ashton Hinchliff , Louise Jameson .