When astronaut Spencer Armacost returns to Earth after a mission that nearly cost him his life, he decides to take a desk job in order to see his beautiful wife, Jillian, more often. Gradually, Jillian notices that Spencer's personality seems to have changed, but her concerns fade when she discovers that she's pregnant. As Jillian grows closer to becoming a mother, her suspicions about Spencer return. Why does it seem as if he's a different person?

Fletcher Reede is a fast-talking attorney and habitual liar. When his son Max blows out the candles on his fifth birthday he has just one wish - that his dad will stop lying for 24 hours. When Max's wish comes true, Fletcher discovers that his mouth has suddenly become his biggest liability.