When a stage play is brought to the screen, especially a play with just one basic setting and only four characters, making it work as a movie can be tricky. “Carnage” works.

The most important credit goes to the writer, Yasmina Reza, whose play “God of Carnage” won the ’09 Tony for best play. With tweaks from director Roman Polanski, her movie script brings us relatable situations and characters direct from our modern day lives.

Next, let’s credit Polanski for taking this one long continuous scene and making it visually interesting. Set in a New York apartment living room (with side trips to the kitchen, bathroom and hallway), the story benefits from good shot selection. The direction gives us varied angles, close ups and wide shots, without calling attention to itself.

Of course, the actors are ones who bring the script to life. Kate Winslet and Christopher Waltz are one couple. Jodie Foster and John C. Reilly are the other. All four deliver excellent performances.

The two couples visit together after their sons have been involved in a playground incident. One couple wants the other to apologize for their child’s aggression. As the discussion continues, other subjects are addressed. Food is shared and later, booze. The couples engage in verbal warfare, first with the opposite couple and then with their own spouses.

Many of us who are married with children have been in similar situations. You want to be nice, but sometimes tensions build. In “Carnage,” there are moments that will make you uncomfortable and there are moments that will make you laugh out loud. You may shift your allegiance and identification from one character to another (and maybe back again).

I like “Carnage.” Despite its being one 80-minute long conversation, it is not boring. Does “Carnage” have a message or two? Maybe. That’s for you and your spouse to discuss on the drive home from the theatre.