(CNN) When police officers pulled over Stephen Jennings in Guthrie, Oklahoma, on June 26, they searched the car and got a lot more than they bargained for.

Jennings was pulled over about 11 a.m. after an officer noticed that his car tags were expired, police say. He alerted the officers that there were a few other issues likely to arise: There was a gun in the vehicle, for starters.

His passenger, Rachael Rivera, was charged with possession of a firearm after a former felony conviction.

Rachael Rivera was charged with possession of a firearm after a felony conviction.

Then, police said, the officers found that the car had been reported stolen and began to dig a little deeper.

And their discoveries: one bottle of Kentucky Deluxe whiskey and one rattlesnake.

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