The Crystal Key is a traditional graphic adventure game with a fairly straightforward plot. Earth is threatened by an alien race once again, as a radio telescope picks up transmissions warning about an aggressive race. A strange spacecraft appears in orbit, deploying satellites. The planet's environment is adversely affected, as tidal and tectonic activities begin to go out of control. It's your job to take a new type of spacecraft and find a way to put a stop to the menace.
The storyline sounds like it would be filled with much more action than there is. Truth be told, the game is much more like Myst - most of your time is spent alone searching barren areas for objects, clues, and yes - puzzles. There is limited interaction with others, but what exists is tightly scripted and you'll find yourself solo throughout most of the game.
The Crystal Key runs in 640x480 mode in (mostly) full screen, or a portion of your screen if your resolution is set higher than that. The environments you explore are made from static images of pre-rendered objects and areas. The look is attractive, although a few of the areas appear a little washed-out.
You navigate the game entirely with the mouse. You click on an area to move to it, and from that spot may pan 180 degrees around as well as up and down. There are transition scenes that take you from spot to spot. Rather than use a new or interesting game engine, the game uses QuickTime technology, making the game PC and Mac compatible, but severely limiting interaction. The cursor changes when you may interact with an object or location, or move to a new area. Inventory is collected in a container, displayed at the bottom of the screen. Clicking on an object highlights it, then to use it you click on a hotspot while it is selected. There's nothing unusual or innovative about any of this, we've seen it all before.
To get from place to place, you need to first find the crystal key mentioned in the game's name, then use it to unlock gateways. Collecting items allows you to progress, and you'll find a number of puzzles along the way. Most of these puzzles are of the "find the pattern and use it somewhere else" type, rather than the brain-teasing logic kind. While the plot of the game is interesting, this kind of puzzle-solving gets somewhat repetitive and makes the gameplay fall a bit flat.
Technically, the game needs a LOT of work. The CD is read from very slowly, making pauses between transitions and interactions painful. Load times are extremely long. You may save your game at any time, but are unable to simply continue from where you left off. In order to resume, you must go through the process of restoring the game from the point at which you just saved. With the insanely long load times this game is capable of, that is a lot more tediousness than is necessary. And you WILL want to save often, because the game can and will lock up or crash at inopportune times. These are known problems, and at the time of this writing a patch has already been released to help clear it up. Out of the box, the game is playable but unstable.
Ultimately, the Crystal key is a standard adventure game with a decent story but stuck with a QuickTime-based engine. The game is interesting, but there is very little interaction with other characters.