Following two delightful “Despicable Me” movies about evil genius Gru and his horde of goggles-wearing little servants, the minions, Gru’s supporting characters star in the “Despicable Me” prequel “Minions.”

Perhaps reflecting the size and appearance of the prequel’s principal characters — minions Kevin, Stuart and Bob — “Minions” is less inventive and entertaining than 2010’s “Despicable Me” and 2013’s “Despicable Me 2.” Despite the shortcomings, the constantly moving “Minions,” packed with minions action and slapstick, is still fun enough to keep kids’ eyes on the screen.

The earlier “Despicable Me” movies are driven by an all-star ensemble voice cast including Steve Carell, Russell Brand, Kristen Wiig and Julie Andrews. In “Minions,” the minions do most of the talking. Only one voice actor, Pierre Coffin, the film’s co-director, provides the minions’ voices.

Cute though the minions are, the nearly featureless little yellow guys and their denim overalls uniforms are, by design, one-dimensional. In the character department, they can’t compete with the eccentric likes of Carell’s Gru, Brand’s Dr. Nefario and Wiig’s Miss Hattie.

The “Despicable Me” films also succeed through stories that both amuse and move audiences. That’s especially true of the original, which tells of Gru’s transformation from despicable villain to loving dad. But the minions do very little evolving in their movie, even though the new film presents minions history from the beginning of time to the 1960s.

That quick historical overview, casually narrated by Geoffrey Rush and co-starring a T-Rex and Napoleon, takes the minions up to the colony they establish in Antarctica in the 19th century. They’ve grown unhappy there, knowing their true purpose is to serve evil masters such as Gru.

Minions on a mission, Stuart, Bob and their leader, the brighter-than-the-average minion Kevin, leave Antarctica in search of a new evil boss. Walking most of the way, they eventually reach New York City and, later, London.

“Minions,” as if to compensate for its lack of colorful characters, or maybe appeal to the grandparents who’ll bring grandchildren to see the movie, accompanies its on-screen action with hits of the ’60s. The soundtrack includes The Turtles, The Rolling Stones, The Doors, The Box Tops and The Kinks.

There’s also an especially fun use of the title song from the musical “Hair.” This movie must have a huge music licensing budget. Despite whatever nostalgia value the film’s oldies may bring, the incessant ’60s songs become overkill.

Because Gru has yet to enter the minions’ lives, the prequel introduces Scarlet Overkill, the world’s first female super-villain. Given voice by Sandra Bullock, who’s usually a fine comic actress, Overkill falls far short of Dru’s villainy and comedy. Next to the crazily seditious Gru, Overkill and her personality, lines, gadgets, castle in England and evil ambitions are disappointingly flat. The same goes for Jon Hamm’s Herb Overkill, the movie’s poor substitute for Dr. Nefario.

Which leaves the minions to save the movie and, as expected, the day. “Minions” isn’t a slam dunk, but it is a win, especially for that core kids audience.