Ensign O' Toole ran on NBC for only 32 episodes during the 1962-63 season with reruns continuing through September 1964. It aired Sundays at 7:00 p.m. opposite CBS' "Lassie" and reruns of ABC's "Father Knows Best". The show was based on the books "All the Ships at Sea" and "Ensign O'Toole and Me" both by William Lederer, who served as a consultant on the series. The action took place on the fictitious "USS Appleby". The ship was portrayed by the real-life U.S. Navy destroyer USS Frank E. Evans (DD-754), which was commissioned on February 3, 1945. Tragically, a few years after the series, the ship was cut in half in a collision with the Royal Australian Navy aircraft carrier HMAS Melbourne on June 3, 1969. Her bow sank almost immediately, and her stern was sunk as a target in Subic Bay in the Philippines. 74 of the crew perished. Following the series, star Dean Jones went on to be a top Disney star from 1965-77.
Reflecting upon the series, "Ensign O'Toole" had a talented cast of character actors but a star ill-suited for comedy. When the star of a sitcom isn't very involved in the laughs, it's hard to be successful. Nevertheless, there are a number of comical, enjoyable episodes found within the series. Some of the best, in my view, are in order of broadcast: "Operation Benefit", "Operation: Impersonation", "Operation: Souvenir", possibly the funniest scene in the series in wrecking Stoner's den at home in "Operation Re-enlist", and "Operation: Arctic". If you sit down with the series without high expectations that other military sitcoms of the era present, it's an enjoyable show.