Sisters Kat and Jo realise there’s a zombie apocalypse in Birmingham, but gamer Kat has a plan: zombies can’t swim - water is the safest option, and narrowboats move just marginally faster than zombies. Jo is unconvinced, until the guy she just slept with (Jude) turns into a zombie!
Jo and Amar go on a mission, while Kat meets her gaming idol, who soon turns into a zombie. As things get more frantic, the girls realise strength may be in numbers.
The gang arrive at the hotel where Sunny and Amar spent their stag weekend. Amar insists that they check if their mates are alive, while Kat makes Jo stay and guard Dorothy.
Kat worries about sharing a kiss with Sunny with Zombie Jude still on their trail. Meanwhile, the gang encounter another boat, which Jo decides to stay on to avoid Kat's bossiness.
The gang are taken to the evacuation centre, where they meet Rob, who is looking for Jude, who he thinks is patient zero. Soon, Jo is bitten, but she shows no zombie symptoms...