The missing element that must be rediscovered to create some new history for this soon-to-be forgotten fixture.

In our intellectual life, a missing element has been study of empire.

Thanks to a poet (born 1859), it has drawn visitors intrigued by a missing element.

There's obviously a missing element to him and this tour could be really key for that if he doesn't get picked.

In its words they identify the missing element of a time-space equation enabling them to travel to the alien destination.