A "collector" from Earth-19 arrives to take H.R. to pay with his life for traveling between dimensions. While Cisco challenges her to a trial by combat, Iris sets out to make her mark on the world before the future that Barry saw comes to pass.

Barry, Cisco, Caitlin, and Julian travel to Gorilla City on Earth 2 to rescue Harrison. However, they are soon captured and Barry is forced to fight a battle to the death against the gorillas' ruler, Solovar.