Ask any fan of the six Star Trek films starring the cast of The Original Series is most "fun," and the answer will likely be The Voyage Home. The fourth film in the series was a time-travel romp with a heavy environmental message. However, it was also a rarity in that the typically troubled Star Trek movie sets were free of all arguments -- except about which animal to save from the past.
Source：https://www.cbr.com/star-trek-iv-voyage-home-biggest-fight-animals/
