WWE continued the mystery storyline with Roman Reigns on this week's SummerSlam go-home edition of WWE RAW, as seen in the video above.

Samoa Joe confronted Reigns in the back parking lot of the PPG Paints Arena in Pittsburgh, PA until a car came speeding at Reigns. Reigns jumped back into his SUV as the car crashed into the rear driver's side. The car then sped off.

There has been some fan speculation that the mystery angles will lead to Joe and Reigns vs. Rowan and Daniel Bryan at SummerSlam, instead of the reported Bryan vs. Reigns singles match. Joe showed immediate concern for Reigns after the attempted attack, and looked as if he wanted to get revenge on the mystery driver.

Furthermore, fans on social media pointed to how Rowan could be seen wearing a black hoodie in a replay of the mystery attack on last Tuesday's SmackDown, as seen below (thanks to Wrestling Inc. reader Jeramis Briggs for the photo). It's believed that Rowan may be revealed as the mystery forklift driver that tried to knock the structure over on Reigns last week. The big reveal looks like it will take place during tonight's go-home edition of SmackDown from Detroit.

Jeramis Briggs contributed to this article.