This is the sixth and final film of the series produced by Universal that included Donald O'Connor, and director Arthur Lubin, who created the sequence. It would be charitable to state that this entry is up to the best of its antecedents, as O'Connor's tongue-tied routine as the chowderheaded sidekick of Francis the talking mule has become rather exhausting for audiences by the time of this release. Army lieutenant Peter Stirling (O'Connor) is advised by Francis that the mule has been "drafted" into the Navy and is positioned as surplus to be auctioned at the Coronado (Calif.) base. While attempting to regain Francis' freedom, Peter is mistaken for a lookalike bosn's mate, Slicker Donovan, is captured by the Shore Patrol and must then reestablish his correct identity while disinvolving himself from various examples of pulchritude with which the rakish Slicker has supplied him by default through their personality exchange. These latter include several of the studio's most highly considered contract starlets, including Martha Hyer, Leigh Snowden and Myrna Hansen, with the always enjoyable Virginia O'Brien attempting a comeback of sorts while restricted to a single scene. The ever efficient Lubin obtains maximum mileage from the dual performance of O'Connor, who stated after the film's completion that he found troubling the larger volume of fan mail received by the mule when compared with his own. Perhaps more telling is the failure of the popular actor to develop his character, a lack made clear by his adroit variant as Slicker. There is also a significant reduction in the use of Francis, and the minimal dialogue given to Chill Wills (his voice) lacks wit and is consequently delivered with scant spirit. Contributing most to the movie's potential appeal are early appearances of subsequently well-known actors, including Paul Burke, David Janssen, Martin Milner and, in his first credited role, Clint Eastwood. Despite the potentially interesting identity crisis involving O'Connor's two roles, it is plain that termination of involvement in the series by the director and star is a move to guard against further erosion of the lead characters' appeal