Before the outbreak, this retail store sold clothes, jewelry and accessories, as well as household products. In the basement of the store was access to the city's sewer and maintenance tunnels for storm drains which helped prevent the building from flooding. There was also a shipping and receiving dock along the side of the building which allowed the delivery of products. When the apocalypse began and people where fleeing to the city for protection, the store was shut down and secured until the crisis passed.
When Glenn and a group of survivors ventured into the city for supplies, they hear Rick Grimes shooting off his gun at the walkers which draws attention to more and more walkers. The group needing to take shelter, break into the building and rest while Glenn aides Rick to get out of the tank and take cover with them in the store. Andrea, one of the survivors on the supply raid, blames Rick for trapping them, Rick feeling somewhat responsible helps devise a plan to get everyone out safely using a truck from a nearby construction site.
After Rick and the group leaves Merle behind due to him being very troublesome and difficult to control, Rick feels obligated to go back for him. He goes back to the rooftop of the department store to find him, only to find that Merle cut off his handcuffed hand and fled the roof.
Rick, Glenn, T-Dog and Daryl then follow a trail of blood leading to where Merle had cauterized his stump.