When Lara find the clock, it unlock the hiding place of two pieces of a sacred icon, The Triangle Of Light.

The triangle was forged from metal found in the crater of a meteor that had fallen to Earth at the exact moment of the previous alignment of the nine planets. The people of the Light built a great city  in this crater where they worshiped the triangle for its ability to control the time, it gives the possessor a power that could be used for a good or great evil. Their abuse of this power led  to the destruction of the city.

To be sure no man would ever again wield this power, the triangle was split into two pieces and hid at opposite ends ot the Earth.

In a temple on the ancient Khmer trail in Cambodia, there is the Tomb Of The Dancing Light, where the first half of the triangle is hidden.

From the secret society known as the Illuminati, devious dangerous men who seek to fulfil an ancient prophecy by reuniting the two halves and attaining the triangle's awesome and terrible powers.