Dolph Springer wakes up one morning to realize he has lost the love of his life, his dog, Paul. During his quest to get Paul (and his life) back, Dolph radically changes the lives of others: a pizza-delivering nymphomaniac, a jogging-addict neighbor in search of completeness, an opportunistic French-Mexican gardener, and an off-kilter pet detective. In his journey to find Paul, Dolph may lose something even more vital: his mind.

Iconoclastic, take-no-prisoners cop John McClane, for the first time, finds himself on foreign soil after traveling to Moscow to help his wayward son Jack - unaware that Jack is really a highly-trained CIA operative out to stop a nuclear weapons heist. With the Russian underworld in pursuit, and battling a countdown to war, the two McClanes discover that their opposing methods make them unstoppable heroes.

As Sherlock reels at the reappearance of his former lover, Irene Adler, a series of flashbacks unravel the tumultuous events that led to his downfall into addiction. Meanwhile, he and Joan once again find themselves in the crosshairs of the enigmatic Moriarty.