Two players, two timelines
The Past Within is a point-and-click adventure built entirely around co-op. One of you plays in The Past, the other in The Future, and neither side can be explored alone. You each see your own environment from a different perspective — one player experiences it in 2D, the other in 3D — so what you describe to each other is often the only clue your partner gets. The goal is to work through the puzzles together and uncover Albert Vanderboom's plan, helping Rose set her father's plan in motion.
How a session runs
Both players need to own a copy of the game and have a way to talk to each other, voice or text. You can play with a friend, or find a partner on Rusty Lake's official Discord. Cross-platform play is supported: as long as you can communicate, one of you can be on PC, Mac, iOS, Android or Nintendo Switch while the other plays elsewhere. The game is a co-op-only title, so there is no solo mode to fall back on — if your partner drops out, the run stops there.
What to expect before starting
The game contains 2 chapters with an average playtime of about 2 hours. Expect observation-heavy puzzle solving: much of the work is telling your partner exactly what you see on your screen, since neither of you has the full picture. The tone is atmospheric and unsettling, with thriller and psychological horror elements wrapped around the mystery. For the full experience the developers suggest replaying from the other perspective, and a replayability feature lets you start fresh with new solutions to all puzzles, so a second run is not just a repeat of the first.