From The TimeSplitters Wiki

Mall
Size	Medium
Location	Small-sized Mall
Climate	None
Unlockable	"Mansion" on Normal
Recommended Bots	N/A
Recommended Weapons	N/A

The supermarket features a shop of course, but also the street in front of it, a small warehouse, an alternate entry for wares and what looks like a maintenance area with ventilation shafts above the shop.