From the in-game instructions:
On returning from Egypt, Lara finds her anonymous employer wishes her to travel to Tibet immediately. Her destination is a nameless ancient monastery, which sits high on an escarpment. Lara must secure a priceless ancient vase containing Cinnabar, a substance used in the creation of life-affirming tinctures. Lara Croft is well aware that the supposedly mythical city of Shangri-La is actually rooted in Tibetan folklore, which describes a remote valley inhabited by immortals. Could this legend be linked to her latest adventure?
Run, jump, climb, shoot and think your way through a variety of levels, watching out for the traps, obstacles and enemies that will inevitably hinder your progress as you search for the fabled treasures of Tibet.