You play Connor, a rogue / mercenary (think Han Solo) who ferry's cargo between star systems in the distant future, no questions asked. You been ferrying cargo between Celtrus III and Rigel VII for quite some time when, on one of your runs, you notice a large space craft that wasn't there a few days previously.
After a few more days ferrying cargo between the two planets, you have a gut feeling 'that there isn't something quite right' with the large craft, flying closer than usually you make out the name...
Event Horizon
Asking about it on the planets, you're told that a ship by that name disappeared 17 years ago, rumour has it that it was testing out some new sort of warp drive or teleport or dimension jumping, no one is quite sure but it disappeared and know one knows where it went.
Surmising that you could claim reward money for it, and wondering what you could salvage from the ship you make your way towards it, only to find it strangely deserted. You head for the landing bay, which has the force shield down, and land in the hanger.
You are about to become the one thing you didn't want...
... the saviour of mankind.