If you want any more proof of the importance of a screenplay to a film’s success, we offer for Exhibit “A” the animated film “Missing Link.”

The movie features a talented cast with voices provided by Hugh Jackman, Zach Galifianakis and Zoe Saldana. Chris Butler’s previous writing credit was the highly praised “Kubo and the Two Strings” while his debut directorial effort, “ParaNorman,” also garnered kudos. Butler directed and wrote the script for “Missing Llink” and while the film has its moments, it falls flat when it should soar.

Start with the protagonist, Sir Lionel Frost, an English adventurer whose bravery is offset by his callous disregard for other people’s feelings. As the Brits would say, he’s a git. There’s a nastier word from the UK that rhymes with tanker, but this a family newspaper.

Frost so far has been unable to enter the ultra-snooty Optimates Club run by the appropriately named Lord Piggot-Dunceby (voice of Stephen Frye, who looks like Gregg Allman if he had white hair and a posh accent). Frost tells Piggot-Dunceby that he is going to prove the existence of Sasquatch, aka Bigfoot – the missing link between ape and humans. The two bet that if he makes this discovery he can become a member of the club. Piggot-Dunceby agrees, yet to make sure he wins, he hires an assassin Willard Stenk (voice of Timothy Olyphant) to ice Frost. Sorry, couldn’t resist.

Piggot-Dunceby, who is rotten to the core, would typically qualify as the film’s antagonist but then he disappears for most of the film and Stenk assumes the role of the villain.

Frost leaves London and is aided in his quest to find Sasquatch by a letter. Upon locating the 8-foot-tall, 630-pound furry beast in the Pacific Northwest, he discovers the letter was actually written by Sasquatch, who turns out to be a kindhearted soul who takes everything literally. When Frost says, “You have my word,” Sasquatch asks what the word is. People of a certain age might remember Hymie the Robot from the “Get Smart” TV series. When Maxwell Smart tells Hymie to kill the light, he shoots it. Yes, another ‘60s flashback.

Anyway, Sasquatch, whom Frost calls Mr. Link, wanted to be found and tells Frost that his dream is to unite with his Yeti cousins in the Himalayas as he's all by himself here. Frost promises to take him there but first he needs a map to serve as a guide to where the Yeti hang out in a place called Shangri-La. The map is now in the possession of Adelina Fortnight (Saldana), the widow of his former partner. Frost and Adelina apparently had fling, but she now hates him and won’t give him the map, so, with Mr. Link’s help, he steals it.

But Adelina won’t let Frost get away that easily. She decides to follow him and Mr. Link on their journey. Why? So she can eventually make see Frost the error of his callous ways in order to become a better person. In other words, she exists as a clichéd plot device – the kind-hearted woman transforming the cold-hearted man. Hey, he’s not called Frost for nothing. I hope. One might be tempted to say he evolves. For more plot claptrap, Piggot-Dunceby shows up in the Himalayas. Why? Well, the bad guy has to get his comeuppance, right?

Now it’s unlikely the target audience for this film – children – will care about the nuances and niceties of screenplay writing. But they do deserve more fully drawn characters, literally. Parents of young children might also be turned off by the film’s violence as Frost and Stenk partake in some serious slugfests. There are a few perilous scenes, too.

The film’s saving grace gets provided by the super-sweet Sasquatch, who tells Frost he wants to be called by the name of a human who treated him kindly – Susan. This gender-bending might have the adolescent set scratching their heads, but, hey, it could be a learning experience. It would be cool to see Susan in a better movie where his sweetness gets put to the test. Maybe he could clash with the boy named Sue.

The film’s other plus is its visual prowess thanks to incredible stop-motion animation where the attention paid to detail is so meticulous that it would make your fur stand on end, if you had fur. The nattily dressed Sasquatch is the animators’ showpiece whose oddball look might remind some of Wallace and Gromit. The film’s landscapes are stunning, too.

Impressive visuals are a trademark of movies from Laika Studios, and if you want to see how marvelous a movie can be when striking images get wedded to a superb script, check out its debut feature “Coraline.”

While “Missing Link” isn’t in that league, it has a certain appeal. It asks you to go on a wild adventure with a lovable character, just leave your discerning eye closed.