It'll take place during a ufo craze,
in the late 50's. Era of greasers, squares, cool cars and rock 'n' roll. And lots of intolerant people who don't take kindly to strangers, let alone alien beings.
Or the 60's. With hippies who want to see "bigfoot" released. They'll help the other preds to rescure their bud. And along their adventure are also introduced to another kind of bud.
Either way, a time with less tech, more open minded (stupid) people and great music.
And I wouldn't mind a short scene where they meet Elvis.