Detective School Dropouts

Donald Landsberg hustles through a string of odd jobs in New York City, hoping detective work will finally stick. He reads detective novels constantly, using them as a distraction that frequently derails his employment. The city is a backdrop for his chaotic quest to make a living.

A notice at a telephone booth pulls Donald toward Paul Miller Lorin Dreyfuss's detective school in a rundown office building. Paul has accumulated debts and relies on exploiting candidates, and Donald is the only applicant willing to participate in his scams. The arrangement drags Donald deeper into illegal schemes that strain his integrity.

The two men stumble into trouble with three Italian cheese-making families—the Lombardis, Zanettis, and Falcones. They discover Caterina Zanetti, the woman the Falcones kidnapped, and learn Carlo Lombardi had intended to marry someone else. Carlo has been deceived by a fake letter claiming Caterina loves another man.

The Falcones plot to marry Carlo to Sonia to preserve their cheese empire, while Caterina offers a message to Carlo via Mario Zanetti to stop the wedding. The fake letter has Carlo convinced Caterina loves another man, which the duo hopes to exploit. Paul and Donald decide to deliver Caterina's message to prevent the match.

Paul and Donald drive to the airport to deliver Caterina's message, but they must steal two passports from Japanese businessmen to follow Mario Zanetti onto the plane. They are eventually spotted by the Falcones, forcing them to pursue the plan across borders. The theft marks the start of their increasingly dangerous scheme.

The trio boards a flight to Rome with Mario in pursuit, hoping to pass the message along. During the journey, Mario is poisoned, thrusting Paul and Donald into a new crisis. They must act quickly to deliver the message as they navigate the dangerous aftermath.

Donald loses his wallet in the chaos and becomes a suspect in Mario's murder. Paul fights to keep them out of legal trouble while the Falcones close in. The pair's banter and desperation escalate as they continue their search in Italy.

Persecuted by their own families, Paul and Donald go on the run across Italy and disguise themselves as monks to avoid capture. They keep trying to locate Carlo and get Caterina's message to him. The pursuit is relentless, testing their wits and nerve.

Despite the danger, they manage to deliver Caterina's message to Carlo, confirming that she still loves him. Carlo begins to reconsider the arranged marriage and the Falcones' leverage. The motive to stop the wedding grows stronger.

Carlo wants to cancel the wedding but is blackmailed with Caterina's life if he refuses. This pressure complicates Donald and Paul's mission, pushing them to continue their interference. The stakes rise as the couple's future hangs in the balance.

After a short stopover in Pisa, Paul and Donald push toward Venice for the planned wedding. The journey keeps them on the run as Falcones close in. The scenic Italian settings frame the countdown to the ceremony.

In Venice, Carlo and Caterina finally meet on a canal, and Paul works to free Caterina while Donald subdues Sonia. They swap the 'bride' and create a moment of confusion at the ceremony. The plan hinges on keeping Sonia out of the way long enough for Caterina to be revealed.

The families draw their weapons, but a moment of divine sign convinces everyone to let the wedding proceed. Carlo and Caterina reunite in the church as the ceremony continues. The power of love and superstition overlays the violent tension.

Paul refuses a cash reward of 25,000 dollars, insisting on keeping a pendant he values more. Back in New York, they plan to sell the pendant, only to discover it is worth 300,000 Italian lira. The twist adds a surprising fortune to their misadventures.

The duo returns to New York with a newfound fortune and the pendant's value. They reflect on the strange sequence of events that began with detective training and led to a cross-continental caper. The movie closes with the two continuing their unpredictable partnership.