Third-person graphic adventure in which you play the role of April Ryan, a struggling student artist in the year 2209, recently arrived in the big city of Newport. April is afflicted with strange nightmares, but her nightmares are starting to affect her waking world as well. Only the strange old man Cortez seems to know what's happening. He sends April to another world where magic is real. There, April learns that what she thought were nightmares are real, and that she must save not just one, but two worlds.

The Longest Journey is a huge game, spanning 13 chapters, plus a prologue and epilogue, spread out over 4 CDs. All the usual graphic adventure elements are present, including lots of fairly challenging inventory-based puzzles, pages of dialogue, and bunches of places to explore. To help keep track of things, the game includes a diary, where April records her thoughts about important events, and a conversation log that records the text of every conversation.