Inception isn't a movie you might get right away. On the surface, it's a great thriller and a solid science fiction movie. At its core, however, it is simply a heist movie. Think of it like Ocean's Eleven with some Primer thrown in.
Given the fantasy nature of Inception, it's a great fit as a theme for a D&D campaign and a perfect model for a skill challenge.
This skill challenge begins with a simple premise. Perhaps an enemy of the PCs has information they must get and the only way to get it is to dig into the enemy's mind. Keeping this goal as straight forward as possible makes the whole skill challenge come together.
How the PCs actually invade the dreams of their enemy is up to you. Maybe they acquire access to a special "dream pool" that lets them invade the dreams of their enemies. Maybe an old hag gives them a ritual to do so. How they get there isn't that important. What they do there is.
Like Inception, each of the PCs should have a role. The roles can be determined by the best skills of the PCs and not every role needs to necessarily be present. Some characters can accept multiple roles if need-be. The roles and key skills include:
Because this sort of skill challenge is based on these roles, it quickly becomes clearer what the PCs are able to do. This makes the overall skill challenge more refined than a standard open-ended series of skill checks.
This scenario doesn't necessarily need to only be a series of skill checks. Dreams can take on very violent forms, requiring the party to engage in a battle with the subconscious enemies within the mark. Since this battle takes place during the rest of the dream, it has lots of potential Combat Outs such as convincing the mark to dismiss the subconscious enemies, giving the architect enough time to change the physics of the environment, or many other potential endings.
While you might only use this idea as a single short skill challenge, you might expand this into an entire adventure or even a main source for your campaign. If your players like it, there's no telling how far you can take it.
If you liked this article, please take a look at Sly Flourish's Dungeon Master Tips and Running Epic Tier D&D Games. You can also use these links to pick up Inception, the Dungeon Master's Kit, or the Monster Vault. Need some cool nightmarish monsters? Take a look at the Dreamblade miniatures at Troll and Toad, an official Sly Flourish sponsor.