Gu Xiaojiao, a young girl from 2018 and Lu Ming, a man from 1999, discover that they have both woken up in the same bed at the same space-time. More surprisingly, they realize that they can time travel by exiting the bedroom door. The fun begins when they start to plan a number of changes within these two eras. However, they do not know that their destiny is in the hands of a mysterious person.

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.