A poor relation to Resident Evil, the House of the Dead games follow a similar premise involving mad scientists and the undead, but done in the form of a light gun game, later trounced (ironically) by Resident Evil: The Umbrella Chronicles. House was a modest arcade hit that was later ported to the Dreamcast and Xbox. Presented here on the Wii are parts two and three, but don't worry about the plot as you simply need to shoot stuff.
As with any arcade shooter, no matter how well it's presented, it's always going to follow the same predictable path: zombie pops up, you shoot it, reload your gun, go around corner, zombie pops up, repeat to fade. However, there are certain differences between House 2 and 3.