This is set in Birmingham, at the start of a zombie apocalypse. One of the protagonists is a blonde bimbo, the other is her geek girl sister. This means we get an excuse for the genre-savvy one to give exposition. Since zombies cannot swim, the best place to be is on an island. So the girls find a canal boat, and head south on the canal to London.
There are two more protagonists - a pair of men of colour. They are also genre-savvy, but inept and clueless compared to the women. Their scenes feel reminiscent of Shaun of the Dead (2004) .
The survivors make their way towards London at top speed. Unfortunately the canal barge's top speed is about three miles per hour, which is only slightly faster than the walking speed of a slow zombie. This means that every time the barge stops at a lock point, the zombies start to catch up with them.
The nerdy girl has arranged to pick up a survivalist friend of hers, who she met online. The nerdy boy is a bit cynical about the online friendship - or perhaps he is jealous and insecure. There is a conversation about zombies, which misses the obvious thing that makes these ones different. Normal zombies are only vulnerable to head trauma: these ones are only vulnerable to heart shots, more like vampires.
The survivors discover they got turned around at the lock gates, and are now back where they started. The guys get to find out what happened to the other guys from the stag party. They all end up trapped on the roof of the hotel. Can they jump safely into the canal?
The survivors stop off for supplies at a supermarket. The hot sister used to work there, and the surviving supermarket drone envies her. As has already been established, in this show the zombies' weak point is their heart instead of their brain.
We get a flashback to 27 hours previously. The hot sister had a one-night stand with a Scottish stud named Jude. Now he is the leader of the zombie horde (well, there are five others with him). The others joke that he is stalking her.
The other plot concerns the barge running out of fuel. The good news is, there is a man with a large supply of diesel oil. Unfortunately he demands payment in cash. He wants to use the cash to pay for a retirement, sailing along the canals without a care in the world. In other words, exactly what he is already doing.
The survivors get to the motorway bridge that marks the outer edge of the city of Birmingham. They run into a group of soldiers, and get taken to an evacuation centre. Naturally the nerdy girl compares this to a series of disaster movies which have scenes where, just when it is meant to be safe, things get worse again. Are the army going to murder all the civilians, or will the centre be overrun by zombies?
One of the soldiers is the hot girl's ex-boyfriend. He is looking for her other lover, the zombie she thought was stalking her last week. The authorities think he was Patient Zero, the source of the outbreak. We learn a lot more about the cause of the outbreak - yes, this is well thought-out and intricately plotted rather than just being an excuse for lots of zombie jokes.