Clay was waiting in line for ice cream when people with cell phones went crazy. Cars were crashing, planes were going down, people were killing other people and alarms were ringing. Clay found Tom at the start of The Pulse and found Alice after the chaos has died down. Together they head for Tom's house which is not far from the city. Clay needs to find his son.
After Clay, Tom, and Alice meet the Head and Jordan at Gaiten Academy, they discover huge flock of the phone crazies in the academy stadium . They set the stadium on fire which gained the attention of other flocks and "The Raggedy Man". In the Academy they confirm that the crazies have the power to control normal people and read their minds. Clay is still looking for his son.
After the main group loses Alice they meet Ray, Daniel, and Denise on their way to Kashwak. This other group is also flock killers, which means they have seen "The Raggedy Man". After Ray Dies due to suicide trying to protect a cell phone the others head for Kashwak on a bus. Clay hopes to find his son in Kashwak
After the group reaches Kashwak they blow up the expo center with the main flock of phone crazies inside. To do this the group used dynamite that was planted by Ray in the back of a bus that the group used to get to Kashwak, the detonator was the cell phone that Ray died for. After the explosion Clay leaves the main group to find his son. Clay promises that he will see the group again.
Clay finds his son but something is different, his son is infected. Since the main flock was destroyed the other crazies are acting different. Together Clay and Johnny(Clay's son) continue with their journey.
Something is wrong, Johnny is acting like a "beaten dog". Clay misses the way his son used to be. Clay is contemplating becoming a phone crazy with the cell phone he has. Clay was making the call but as the phone was answered Clay pressed the phone to his son's ear in a hope to save Johnny.