Kamen Sentai Gorider S01 E01 Maze 1: Emu, is dead?

Emu Hōjō, the alter-ego of Kamen Rider Ex-Aid, wakes up and finds himself locked in a mysterious room. Suddenly, five people appear before him. These five people are previous Kamen Riders were supposed to have died or disappeared. Someone has resurrected the Riders as part of a trap!