Mark Mardon, having survived his apparent death during the black-matter explosion, returns seeking revenge on Joe for the death of his brother Clyde... and has the same weather-manipulation powers as his deceased sibling.
Blame (feat. John Newman) — Calvin Harris
Barry and Linda run into Iris and Eddie at a bowling alley. Iris asks Barry and Linda join them as a "double date." Barry suggests Linda write a story on the bowling alley.
At Jitters: Iris asks Barry how he thinks the "double date" went. The conversation moves to Wells. Iris suggests that he's been involved in many unusual events that have happened in the recent past.
At the Central City shoreline, Iris admits her feelings for Barry. He kisses her, calls Cait, then reveals himself as The Flash. Barry runs around the shore to stop the tsunami threatening the City.