In Touto city. It's have strange great wall are separate japan all of 1/3 Touto seito And Hokuto. There is demons call Smash. And Riders. You heard about project build before. And you know what is mean. One day The smash raid is begin you saw 4 people are walked towards them with build drivers and sclash driver.

"I don't feel like losing!" Banjou Ryuga

"Now, shall we begin the experiment?" Kiryu Sento

"The fire of my heart...passion..." Kazumi Sawatari

"Be a sacrifice for a great cause!" Gentoku Himuro

"HENSHIN!!!" They all transform into kamen rider. Build,Cross-Z,Grease And Rogue.