Somewhere in England Samantha, Tony and Charlie encourage each other to play dangerous games. They find their biggest challenge yet when they come across an injured dog trapped in an electrical substation.

In the meantime Kate and her latest boyfriend find themselves on a long weekend in Germany playing games of their own. Will they strengthen or destroy their relationship?

Back in America, long before he moved to England, Richard also played a game, encouraged by a stranger, as part of an scientific experiment. The decision he made would affect his life forever. 

As Samantha delves into her family's secrets she discovers where the true horror lies.