Grill Point is a 2001 German drama film directed by Andreas Dresen. Its original German title is Halbe Treppe, which means Halfway up the Stairs in English, and was the reallife name of the snack bar shown in the film.
Uwe, owner of a snack bar, and his wife Ellen, who works in a perfume store, are friends with Katrin, who works in a trucking agency, and her husband Chris, a radio DJ. Neither marriage is holding together well soon, Chris begins an affair with Ellen. When Katrin discovers this, they try, and fail to solve the problem as a foursome when this fails, the two couples respond to the situation in different ways.
Source: Wikipedia