The Guardian (Don)

"They found it! And the best part is, they don't even know what they found! They just think it's just one gold bracelet! Which means that the magic emerald is MINE! ALL MINE!! (cackles maniacally)"

- The Guardian revealing his true colors.

The Guardian is the main antagonist of the 1998 live-action/animated film, Don.

He is the ruthless, selfish, determined and mysterious leader and ruler of the lemurs who tries his best to make the world chaotic and destroy Madagascar by stealing the emerald for himself.

He is voiced by Jonathan Freeman, who also voiced Jafar from Aladdin.

History
The lemurs of NIMH were experimented on until they eventually developed human level intellect. The Guardian became the most intellectually gifted among his kind so when the rats escaped their cages the Guardian was made their leader.

The Guardian gives Don and his half-brother, Patrick Spinel, a mystical emerald and offers to save her family to repay the cruelty of his family, who was interested in helping the lemurs escape NIMH, and Spinel accepts, but Don refuses.

Upon seeing the emerald, the Guardian, determined to 'lighten the load', becomes greedy, saying that it's nothing personal, reveals his true plan to get the emerald for himself and take over the entire island.

Don swings on a rope towards the Guardian and they both fall. Grabbing the rope, they slide down and land on the platform above the spinning propeller blades. Don lunges at Spinel, but he is easily outmatched by Spinel's strength and expertise in combat, with Spinel quickly gaining the upper hand. Patrick Spinel is easily defeated when Don knocks him unconscious with a boulder, sending him falling into the river. Losing what's left of his sanity, the Guardian grabs an axe to kill Don in exchange for the emerald for profit, and also revenge for foiling his plans. The Guardian swings his axe at Don, who ducks and desperately takes a shard of glass containing the crystal's essence as the Guardian grabs him to finish the killing blow on him. Just as the Guardian prepares to decapitate Don, the latter scratches his arm with the shard, turning the Guardian into a crystallized blue monster. At first, Don thought the Guardian was done for, but was proved wrong when the Guardian appears to still be alive. Fortunately, the Guardian pulls up the chains, hoisting himself into the airplane's propellers, while Don watches the Guardian screams one last time before the propellers shatter him into millions of pieces, destroying him for good.