...which is because it is a complete farce from start to finish. In spite of the fact that the script includes a lion roaming about free in a hotel, a bit of a mad - okay more like eccentric - scientist, the alleged devouring of an older gentleman, a jailbreak, and a combined vigilante/ police man and lion hunt, there is zero stress in the entire film.
Parts of it are pure 60's "hey the production code is gone, let's go wild!" (wild for 1965, that is) stuff that really is pretty tame today as far as sexual content is concerned, including a honeymooning couple that winds up with everyone in the hotel sleeping in their room. This is the last straw for the bride who, as she leaves her new husband says "If mom and dad had started out this way I wouldn't even have been born!" There is a host of talented character actors in the background, such as Edward Andrews as the hotel proprietor, Howard Morris as a guest who thinks that the lion's roar he hears is from neglecting his cat - he even is the first to see the lion, but everyone just assumes it is drunken delusions. Then there is Jim Backus as a rather incompetent police sergeant.
The basic storyline is that Dr. Daniel Potter (Tony Randall) as a researcher at the Braden institute is running from the police who want to impound "Fluffy", a lion who Potter has trained to be as tame as a housecat. In fact, most of the trouble is caused by Potter referring to Fluffy as "his cat". He checks into a residence hotel that is completely booked, but the jet setting Janice Claridge (Shirley Jones) is going to be gone for the night and gives Potter and "his cat" her room. From there the misunderstandings and mayhem begin.
Recommended if you just want to laugh and need zero stress and conflict in your cinema entertainment for once.