As the Avengers and their allies have continued to protect the world from threats too large for any one hero to handle, a new danger has emerged from the cosmic shadows: Thanos. A despot of intergalactic infamy, his goal is to collect all six Infinity Stones, artifacts of unimaginable power, and use them to inflict his twisted will on all of reality. Everything the Avengers have fought for has led up to this moment - the fate of Earth and existence itself has never been more uncertain.
Chaos reigns at the natural history museum when night watchman Larry Daley accidentally stirs up an ancient curse, awakening Attila the Hun, an army of gladiators, a Tyrannosaurus rex and other exhibits.
Hapless museum night watchman Larry Daley must help his living, breathing exhibit friends out of a pickle now that they've been transferred to the archives at the Smithsonian Institution. Larry's (mis)adventures this time include close encounters with Amelia Earhart, Abe Lincoln and Ivan the Terrible.