A UPI news item dated July 3, 1960 reports that while preparing to film a scene on a boat, Lucille Ball fell, struck her head and was knocked unconscious. She was taken to Cedars of Lebanon Hospital for a possible concussion and severe face and leg bruises. Her ex-husband Desi Arnaz rushed to the hospital from his ranch at Corona to be with her. Fortunately, preliminary x-rays of the head, neck and spine showed that the beloved star was not seriously hurt. Bob Hope was quoted in a New York Times article, "This film should have been shot at Cedars of Lebanon Hospital".
The injury to Lucille Ball was not the only problem to afflict the picture. Don DeFore injured his back, requiring hospitalization, and director Melvin Frank broke his ankle playing golf and had to hobble around on crutches. The film's publicist came down with a two-week case of the mumps, Bob Hope smashed his finger, and even the delivery man from Lucy's pharmacy fell into the same tank that the star had. To top things off, a few days after Lucy referred to her Desilu soundstage as a "firetrap," it partially burned down.
Rather remarkably this was chosen for the 1961 Royal Film Performance at the Odeon Leicester Square. Perhaps wisely, HM The Queen gave it a miss and sent her mother and sister instead.