Underdog - Season 3 - Eps 14: The Marbleheads, Part 2
After all the reporters and news crew leave the site of the strange object, two stonehead creatures from the planet Granite, named Gravel and Crusher, emerge from the craft with their Granite Gun. Their mission is to collect 10 slaves to bring back to their planet to work in the rock mines. After reporting in to their fearless leader, Captain Marblehead, the two buffet on some of Earth's stones and marble. They then proceed with their mission and collect 10 slaves, which so happen, include Shoeshine Boy and Sweet Polly. Before they leave for home, they are observed and the army tries to stop them.
About Underdog

Title: Underdog
First Air Date: 1964-10-03
Last Air Date: 2000-02-01
Status: Ended
Rating: 6.2/10 (from 22 votes)
Language: EN
Seasons: 4
Total Episodes: 125
Network: NBC
Genres: Animation, Comedy
Production Companies: Total Television Productions, Leonardo Productions
Synopsis
Underdog is an American animated television series that debuted October 3, 1964, on the NBC network under the primary sponsorship of General Mills, and continued in syndication until 1973, for a run of 124 episodes. Underdog, Shoeshine Boy's heroic alter-ego, appeared whenever love interest Sweet Polly Purebred was being victimized by such villains as Simon Bar Sinister or Riff Raff. Underdog nearly always speaks in rhyme, as in, "There's no need to fear, Underdog is here!" His voice was supplied by Wally Cox.
Cast

Wally Cox

Sandy Becker

Kenny Delmar

George S. Irving

Mort Marshall

Norma MacMillan

Delo States

Ben Stone

Allen Swift