By now, you’ve probably heard about something related to Volkswagen, diesel, emissions, and cheating. Here’s the quick-and-dirty about what happened, how they got away with it on a nationwide scale, and what they’re doing to make up for it.

What happened

VW was found to have mechanically cheated U.S. emissions tests for diesel engine cars. Diesel emissions are fuel efficient but burn dirty. VW couldn’t (or wouldn’t) find a way to keep fuel efficiency high while cleaning up the emissions.

In the U.S. 500,000 cars are affected, including 2009-2015 versions of diesel engine Beetles, Jettas, Golfs and Audi A3s, as well as 2014-2015 Passats. As many as 5 million vehicles worldwide are affected.

How they got away with it…until now

Essentially, the cars knew when they were being tested and software inside the vehicle made it look like the emissions were cleaner than they really were. On the road, the engines were releasing more than 40 times the allowed amount of nitrogen oxide fumes into the air.

What they’re doing to make up for it

German prosecutors are investigating how far up the corporate ladder the cheating was known and condoned. As of right now, no recall has been issued but VW says it plans to refit up to 11 million vehicles affected by the emissions-cheating software. There’s no telling where the cost of refitting the vehicles in addition to the huge hit in reputation will leave the company.