Timeline for the future perfect tense

To me, one of the most gut-wrenching moments in cinema is that scene in the 1979 science-fiction classic Time After Time where Amy Robbins, the love interest of the time-traveling Victorian fictionist H. G. Wells, enters a museum a few days into the future and stumbles on a newspaper that headlines her brutal murder by the serial killer Jack the Ripper. The usually unflappable prototype of today's liberated woman slowly crumbles to the floor in dazed disbelief — a victim of the future suddenly and inexplicably colliding with the present.

Situations like this are the essence of the future perfect, which allows us to project still unrealized events and outcomes into the future. Always, the future perfect refers to a completed action in the future. To get a sense of this, imagine yourself — like Amy Robbins — to have traveled in time and now looks back at actions or events that will be completed after the present time, which is now in the past.