Weird: Truth is Stranger Than Fiction is officially marketed as an adventure game, and contains a few puzzles, but in reality is more of a multimedia encyclopedia of strange phenomena and legends with a Myst-like slide-show presentation.

The player starts in a room full of doors, each leading to different places. These places are filled with objects that, when clicked, display texts, video and audio about weird and unexplained events, mythical creatures and folklore. Some doors are locked, and can only be opened by solving one of the puzzles.