The story begins with a husband throwing a surprise anniversary party for his wife. As the evening proceeds, little things don't make sense. The wife is appalled at the amount of money spent. The husband tries a little too hard to seem happy. Odd looks and gestures pass between guests. One of the caterers seems more than curious about the couple.
When the evening is over, there's body on the floor and we hear complicated explanations of what happened. As the story proceeds, we wonder who did what and whom to believe.
Alibi plays out in three, 45-minute episodes. The action is remarkable not only for elaborate schemes, but also for the range of feeling from noir to farce. The acting is superb with Michael Kitchen, Phyllis Logan, and Sophie Okonedo in the principal roles.