Those looking for a lightgun shooter for the Dreamcast would be far from disappointed.
You are pitched into the roles of Howard Gibson and Jean Clifford, both members of the top-secret Confidential Mission Force agency, or CMF. The story is essentially one giant tribute to Goldeneye. Agares Headquarters has hijacked a satellite and plans to use it for their evil deeds. If you've seen Goldeneye, you won't be seeing anything new. The cutscenes are, as one may expect, delightfully cheesy with atrocious voice acting. Unfortunately, the story mode is a little shorter than that of HotD2. Confidential Mission should only take you about an hour to blow through.
Of course, Confidential Mission is compatible with any Dreamcast lightgun. Just like any rails-shooter, your character is piloted around environments automatically, with you controlling the shooting. Confidential Mission is actually very similar to Sega's Virtua Cop, with rings that form around the enemies, changing colour as they are about to shoot you. Were the game shows its innovation, is in the minigames, in which you are given a task to complete within a certain time limit. This could be breaking a train coupler, shooting a grappling hook, or clogging poison gas vents. You are usually sent on a different path depending on whether you are able to achieve this objective.
Confidential Mission is also unique in that there are many ways to score points. There are many pickups on the ground to shoot that grant score or firepower. When confronted by an enemy, you can shoot him once and move on to the next, or, you can hit him repeatedly for extra points. You can also aim for the "justice shot" by shooting the guns out of your enemy's hands.
The music is cheery and upbeat, and the graphics are quite good, and the game never drops a frame, despite the many things that can be going on at once.
Apart from the mission mode, there is a training mode, which can grant you unlockables. The only problem with these is that they're often frustrating and sometimes nearly impossible. They're really just an extra feature though, so no harm, no foul.
In the opinion of a Dreamcast fan who owns both Confidential Mission and House of the Dead 2, Confidential Mission is all around a much better game. But, of course, this is only an opinion. If deciding between the two, it may be a good idea to check YouTube. But, if you're in the market for a rails-shooter, you can't go wrong with Confidential Mission.