The Last Legion, a sword-and-sandal spectacle from those epic-loving De Laurentiises, invokes a lot of better movies on its circuitous trip from the Roman Empire to the Arthurian legend, but it doesn’t do the one bit of borrowing that could have made this journey enjoyable.

The film, in which a handful of loyal warriors try to protect a youngster who is the last Roman emperor, has beloved images and gimmicks that suggest Star Wars, Raiders of the Lost Ark, Crouching Tiger, Hidden Dragon, even Planet of the Apes. But, alas, the ragtag band doesn’t have any of the lovable insolence of, say, Pirates of the Caribbean. Its few attempts at humorous camaraderie fall flat, leaving you wondering why this grim group wants to keep living at all.

It all starts with the boy: Thomas Sangster as Romulus, a 12-year-old with the blood of Caesar in his veins. This dour child wouldn’t inspire anyone’s protective instincts, and he doesn’t exactly show signs of greatness. In the climactic battle he stands by idiotically while his chief protector (Colin Firth) is beaten nearly to death by a nasty Goth, then he intervenes with his magic sword.

Aishwarya Rai isn’t even worth a spoiler alert, so obvious is her surprise emergence from beneath armor as the Firth character’s mysterious sidekick. Yes, she’s a she, and no, her martial-arts-style fighting abilities aren’t very convincing as filmed by Doug Lefler, the director. Ben Kingsley does an Obi-Wan Kenobi impersonation as a mystical fighter turned teacher who fills Romulus’ head with airy advice.

Dino De Laurentiis gets a presenter’s credit, and his wife, Martha, and daughter Raffaella are producers, so the grand ambitions here are understandable. And misplaced. This might have made a good children’s film.