Five webisodes were released from 22 December 2010 in the run-up to the fourth series, which began airing on New Year's Day 2011 in both the UK and US.

ITV released the webisodes, each 2–4 minutes long, written by Sarah Dollard, that provided background to the upcoming series 4.

When Connor looks up old friend Duncan, he doesn't expect to find him obsessed with creature sightings. Warning him of the elusive dock creature, the pair track it down to the docks, only to find evidence of a fresh kill. With Abby and Matt arriving to help, they find the creature after a tense chase through a container yard. Will Connor's quick-thinking and bravery earn him back his place on the team?