It’s easy to picture Telly Savalas sharing drinks with friends, proposing a comedy-adventure set on a Greek island so they could all soak up some sun while he displayed his clear affection for his heritage. Fortunately, David Niven's personal struggles with alcohol near the sea prepared him well for the role, and Roger Moore was eager to do something beyond his usual style, so the group headed to Rhodes, accompanied by Stefanie Powers and Elliott Gould in an effort to boost international sales. Niven plays an archeology professor; Moore is the head of an outdoor excavation/prison, and their host is a local rebel who wants not only to eliminate the Nazis but also stop them from stealing ancient Byzantine treasures supposedly hidden by monks in a monastery high up in the mountains. "Dane" (Gould) and "Dottie Del Mar" (Powers), while on a USO tour, find themselves stranded when their plane goes down; she entertains the troops while her companion, more interested in profit than caution, tries to help incite an uprising. The film is generally cheerful and entertaining, with everyone appearing to be having fun, and there's some beautiful photography of the island – I wonder how they constructed that monastery? There’s plenty of exaggerated acting, noticeable accents, and Michael Sheard (following his role in "Star Wars") seems comfortable playing a memorable sergeant. Lalo Schifrin's music attempts to capture the feel of Mikis Theodorakis's “Zorba” theme, and I mostly found their silly seaside adventures enjoyable.

Source on TMDB