The House of the Dead is a great game, let's get that out of the way from the start. In fact, alongside NiGHTS and Burning Rangers, it's one of the highlights of the SEGA Saturn's lifespan.
In the 90s, if there was something SEGA knew how to do, except making awesome platformers starring blue hedgehogs and fighters, it was lightgun games. Alongside countless licensed movie efforts (I keep hearing The Lost World is a highlight, however I've never played it myself), SEGA had two series which found their home originally on the black box: Virtua Cop, and House of the Dead.
The House of the Dead was exactly what you'd expect - lots of gore, plenty of zombies to shoot with civilians to save, B-Movie style plot and voice acting, it was like Resident Evil, only as a lightgun game (indeed, RE's Survivor duology can't hold a candle to HotD, although RE: Dead Aim comes close). You explore Curien Mansion, the titular House, by way of following an on-rails track through each level, making sure zombies stay dead, civilians are saved and lives, for some reason denoted by burning lanterns, are kept.
If you've never played the original game before, it's now actually quite hard to come by. Arcades (remember those?) seem to focus more on the later entries, and it's never seen a home console release outside of the Saturn. Here's hoping that, with SEGA's new focus on releasing their old titles digitally, The House of the Dead sees the light of day again.
Requests between 28th Nov and 4th Dec