Michigan City was a beach town once. The kind of place where Chicago families drove ninety minutes to eat overpriced ice cream and complain about sand. That was before the Indiana-GLMZ Border Compact of 2171, which designated the town as the primary ground-transit checkpoint between the Indiana Exclusion Territories and the southern edge of the Great Lakes Metropolitan Zone. Now Michigan City is a throat -- a narrow passage through which everything heading north must be swallowed, scanned, and either admitted or expelled.

The checkpoint infrastructure dominates the lakeshore like a brutalist cathedral. Three kilometers of reinforced inspection lanes, biometric gates, cargo scanners capable of detecting a single unregistered neural implant in a shipping container of ten thousand. The old beaches still exist on the east side, technically public, but the sand is grey with industrial runoff and the water carries enough heavy metals to set off a Geiger counter's more anxious cousin. Ringo Systems holds the border security contract, and their Sentinels patrol the inspection lanes with the relaxed confidence of people who know that everyone passing through needs them more than they need anyone passing through.

The town itself has stratified around the checkpoint economy. The north side -- the admitted side -- is a service district for transit workers, truckers waiting on cargo clearance, and the small army of lawyers who specialize in border disputes. The south side is where you go when you've been denied entry. It's a limbo district of temporary housing blocks, unlicensed medical clinics, and fixers who sell forged transit papers for prices that climb every time the border protocols tighten. The locals call the south side the Waiting Room. Some people have been waiting for years.