In this episode, Lindsey Chapman will bring this story up to date since this episode was first broadcast in 2008, offering some up to date thoughts on all things molluscan.

It is not often on the Living World that the largest or biggest of any species is discovered. Yet in this episode Lionel Kelleway is in search of a large slimy creature. Though locally common across Britain's ancient woodlands, this slug is very much at home in the warm damp woodlands of Dartmoor and is the world’s largest ground slug, the “Ash-Black” slug. This mollusc is known to reach up to a length of 25 to 30 centimetres. Lurking under the bark of dead trees during the day, at night they slip obsequiously into the open looking for fungi of all kinds to eat. Guiding Lionel is renowned Dartmoor, naturalist John Walters who explains these large slugs are quite easy to identify by their characteristic dark edged sole, with a pale, ash coloured stripe running through the middle. Their presence is an important part of the ecosystems that keep ancient woodland alive. As if encountering this leviathan was not enough, the duo also stumble across Britain's largest ground beetle, Carabus intricatus.