The episode began when two cavalry officers are bring supplies to Fort Dodge when their wagon is ambushed and the officers are killed. In the back of the wagon, hid in a sack of vegetables, is the payroll for the fort. The payroll money was a secret so it appears to have been committed by someone with inside information.
When the Cavalry commander threatens to occupy Dodge City and place the town under martial law unless the criminal(s) are captured, Matt intervenes and ask the commander for forty-eight hours.
When Kitty gets suspicious of a new girl, Jennie Lane, that she recently hired- she tells Matt that Jennie has been seeing a clerk at the fort. Matt begins to piece together the circumstance and soon sets up a trap to find the persons involved.
The episode set the ending up rather nicely with much anticipated. However when we finally get to the climax, it was so quick and disappointing that it made the entire show suffer. The story was nice- just wish they could have spent more time on the ending to make the show complete. But since that did not happen we are left with a story that came to such a abrupt ending that viewers felt disheartened.
Note- The episode was titled 'Carmen' comes from the radio version where the female character was named Connie. Not sure why they felt the name needed to be changed to Jennie.