In the final installment of the Defenders of Time science fiction trilogy by Gene P. Able, The Aliens Step In, everything changes. 

The surface structures of the US Time Travel facility, once the crown jewel of human innovation, disappeared without warning. No sabotage. Just gone.

Inside the last remaining Time Chamber, which is underground, a classified team races to identify the breach. The chamber offers brief protection from timeline collapse, but its shield is already weakening. If the damage isn't reversed soon, history will rewrite everyone, including them.

The Time Travel team determines that China successfully went back in time to erase the American Time Travel operation. The US Team goes back in time to restore the past which only makes it worse. Political alliances fracture. Global conflicts erupt. The timeline spirals toward a future that should never exist and endanger the greater Universe.

And then it happens.

A presence materializes inside the chamber. Startling, powerful, unlike anything seen before. His name is Sonsa Tabback.

He delivers an ultimatum – Earthlings must end all Time Travel activities. He takes Earthlings to his ship and demonstrates he can enforce this demand. He however proposes a visit to his home world and offers a gift that would change Earth's future forever. But only if humanity agrees to eliminate Time Travel permanently both to the past and into the future.

The Aliens Step In is a cinematic science fiction thriller built on global stakes, interstellar diplomacy, and edge-of-your-seat tension. Perfect for fans of Tom Clancy, Crichton, and The Expanse.