Near the end of the fourth season, there were three unrelated stories of extraterrestrial invasion in three weeks.

The first thing that comes to mind when looking at these photographs is an extraterrestrial invasion.

"The bank robbery's not scheduled until five o'clock, and the extraterrestrial invasion won't start until midnight."

A few days into the snowfall, they learn that the phenomenon was caused by an extraterrestrial invasion to Earth.

Its theme is that of extraterrestrial invasion.

Others came closer to the truth, imagining that they were warnings of an extraterrestrial invasion.

Colins and Anna got married and set up an organization that helped in the prevention of extraterrestrial invasion.

"Dark Skies," at 8, presents the notion that every major American event of the last two generations was a result of an extraterrestrial invasion.

The story depicts an extraterrestrial invasion in a small California town.

This machine becomes an important ally in the battle to save Tony's sister and stop the extraterrestrial invasion before it's too late.