Sly Cooper 3: Honor Among Thieves follows Sly's quest to reclaim a birthright that has been passed down through the Cooper family for generations. He has learned from an old friend of his father's that the Cooper family has been stowing their stash in a mountain vault that is now under the possession of a deranged scientist-baboon.
Sly and one of his best friends, Bentley, must gather a crack team of thieves to steal back what is rightly his. The game takes you across the world from Venice to Australia as you collect people that each have their own strengths. The first stop is to find and win back the lost third member of the Team Cooper, Murray. Murray left after the events of Sly 2: Band of Thieves when he felt responsible for Bentley's injuries that now have the explosive-expert turtle wheelchair-bound.
Besides Murray, you will collect his aboriginal mentor from the outback, and two or three other characters. Each of these characters has one or more unique gifts that make them a great and necessary asset to Cooper's plan to retake the vault. These abilities range from pure strength, to the ability to turn into rocks and trees in order to hide from guards, to laying bombs that can lay waste to baddies in your path.
Cooper's path to reclaim his rightful wealth will be full of a wide variety of missions. Not only will you have to sneak your way through cities collecting booty or cracking safes, but will also have to pilot boats down the Venetian canals, fly fighter-planes over farmlands and take pictures of crime lords as they do dastardly deeds.
Each episode also contains at least one mission that can be viewed using 3D-glasses (included) for added effect. The use of these glasses is an interesting effect. Typically these missions involve you weaving through laser beams, crawling through rotating cork-screws or walking through leaky steam pipes. With the glasses on, there is a noticeable difference and the 3D effect is quite apparent. If you decide to take the glasses off, you can either carry on with the screen like it is (really it looks normal with the colors slightly off), or you can restart the mission without the 3D effects and it looks like any other mission.
Honor Among Thieves also has several multiplayer modes. Cops & Robbers puts one player in the role of Sly while the other controls the foxy copper, Carmelita. The two of you race around town while Sly collects goods and Carmelita tries to stop him. Co-Op mode has two players working together to break into a security system and fight enemy after enemy as you work your way to the exit. Biplane Mode has Sly and Carmelita taking to the airways to see who can rack up 10 kills first. Pirate Battle lets you control either Sly or Bentley as you steer and repair your ship trying to sink your opponent's boat three times.