A researcher from this century travels back to New Jersey, Earth, in the 22nd century, where his time pod is stolen by an individual named Berlinghoff Rasmussen. The unscrupulous Rasmussen uses the pod to travel to the 24th century.

Scientist Kal Dano invents the Tox Uthat, a quantum phase inhibitor with enormous weapons potential because of its ability to halt all nuclear reactions within a star. An attempt is made to steal the Uthat by two Vorgon criminals, so Dano travels back in time to the 22nd century, hiding the device on planet Risa. The device remains there until unearthed by archaeologist Vash, whereupon it is destroyed by Enterprise captain Picard in 2366.

Radiation levels in the Andromeda galaxy are expected to reach intolerably high levels within ten millennia, according to scientists of the Kelvan Empire. Agents of the Kelvan Empire were dispatched aboard a multigenerational spacecraft to explore our Milky Way galaxy for possible colonization.