When obsessive-compulsive detective Adrian Monk is let go after the latest round of budget cuts, he will not stop investigating, even without pay, especially when Captain Leland Stottlemeyer is framed for the murder of another cop.
Ona a side trip to France, detective Adrian Monk takes a tour through the historic underground world of the Parisian sewers, where he encounters a catacombs filled with ancient human remains, including one much more recent skull bearing evidence of murder.
Reverting to his OCD habits when his therapist, Dr. Kroker, heads off for a conference in Germany, an anxious Adrian Monk follows his shrink to Europe and comes face to face with a man who might be the person responsible for his wife's death.