MOSCOW — The scene was straight out of “C.S.I.,” food safety edition.

At a McDonald’s in a provincial town northwest of here, health inspectors in lab coats swooped in for a surprise check, clipboards, test tubes and cotton swabs in hand. After finishing, they promptly filed a lawsuit to stop the fast food chain from selling certain items across all of Russia.

The offense: The calorie counts on the cheeseburgers, Filet-O-Fish, berry ice cream and other items did not match the amount listed on the paper tray liners.

As geopolitical tensions continue to simmer over the Ukraine crisis, Russia isn’t just a perilous place to do business. It is entirely unpredictable.

Some companies like Exxon Mobil and the energy services firm Schlumberger have been ensnared by the Western sanctions intended to cut into core Russian industries. Others such as Visa and Condé Nast have been hit by the tit-for-tat response by the Kremlin.