In James Griffiths’ delightfully eccentric comedy “The Ballad of Wallis Island,” Charles (Tim Key) is the kind of sweet human being you instantly want all the good things for. It might be tough, for instance, to feel genuinely happy that someone who isn’t in urgent financial need had won a big-time lottery twice — unless of course that person is Charles. The soft-spoken chap is so warm-hearted, open-handed and full of puns that you won’t actually mind that good fortune has repeatedly found Charles and allowed him to retire to a gorgeous (fictional) Welsh island, after he traveled all around the world.

A co-writer (along with co-lead and his longtime comedy partner Tom Basden), Key is the main reason this cozily windswept and romantically sea-sprayed fable — based on the trio’s 2007 short film “The One and Only Herb McGwyer Plays Wallis Island” — succeeds in earning the goodwill of the audience.