The newly released Homefront: The Revolution is a shooter about a war-torn Philadelphia under North Korean occupation, in which players have to rouse the population into an uprising.

But hidden within that game is another game: a shooter about traveling through time.

TimeSplitters 2 was created by developer Free Radical Design waaay back in a time when an Xbox was just an Xbox and there had only ever been two Playstations. It was also a well-loved, goofy little game. Though the years have passed as Free Radical became Crytek UK, and then Dambuster Studios, the history of galavanting through history is still there—and it shows up in Dambuster’s Homefront, which is about an alternate history.

All that to say that if you can find the Easter egg in Homefront, you can enjoy a little bit of what made Free Radical so cool all those years ago. The video above, from Eurogamer, will show you what you need to do. Just be careful not to create a paradox and undo all of existence while you’re traipsing through time.