Together with Frank and Hannah, the only other survivors that Jim and Selena find in London, they head north in a taxi following instructions from an emergency radio broadcast. Outside of Manchester they meet Major Henry West (Ecclestone) and his men -- who gun down Frank who has become infected when dripping blood from a corpse falls into his eyes.
The remaining survivors are taken to a mansion that the soldiers have garrisoned, and finally the Major's plan comes out -- that to keep his boys happy, he needs women around to act as their sexual slaves. Jim tries to escape with the girls, but they are soon captured. With one other guy who doesn't agree it's such a good plan, they are taken outside to be killed.
Jim manages to escape successfully this time and jumps the outside wall. Lying in a ditch he looks to the clouds -- and sees a plane.
Filled with hope, he hatches a plan. He returns to the mansion and unleashes one of the infected soldiers who has been chained up outside. The infection spreads through the mansion, with a little help from a rageful Jim.
Jim, covered in blood, makes his way to the girls and murders their guard. Selena breaks her promise and hesitates before she kills him, thinking he has turned. Instead they kiss and make their way out.
The Major shoots Jim but the infected soldier manages to get his hands on his old leader, and the other survivors leave him behind as they race off in the taxi.
Jim is rushed to a nearby hospital where Selena desperately tries to save his life.
28 days later, Jim wakes in bed -- this time in a cottage in the Lake District. The girls are busy at work stitching something together. Suddenly they race outside and lay down their creation to spell out the word "Hello" as a jet flies overhead. Infected people are in the distance, dying of starvation.
In most of the alternative endings, Jim dies in hospital, which is a little depressing, and either the girls leave to fight the world alone -- or they make it to the Lakes alone, where they can signal the Finnish pilot for help.