Hartley Sawyer is joining the cast of “The Flash” Season 4 as Ralph Dibny — also known as the Elongated Man.

The Elongated Man is one of the Flash’s allies — who by day is a fast-talking private investigator and by night costumes up to patrol the streets and fight crime thanks to his ability to stretch his body to any shape or form. Sawyer will appear in a recurring role through Season 4, and will use his abilities to help Team Flash solve one of Central City’s greatest mysteries.

The news of Sawyer’s casting comes after a slew of other similar announcements during San Diego Comic-Con. Danny Trejo — known for “Machete” and “From Dusk Till Dawn” — will play Earth-19 bounty hunter Breacher in Season 4 while Neil Sandilands will play Clifford Devoe, aka the Thinker, the big bad of the season. Kim Engelbrecht was also announced to play the Mechanic, a highly intelligent engineer and the Thinker’s right hand.

During “The Flash’s” Comic-Con panel, executive producer Todd Helbing said they would be returning to a lighter tone for Season 4 after Season 3 got increasingly dark, and expressed his excitement for the series to have a non-Speedster season-long villain.

“With three Speedsters in a row, this year it’s the fastest man alive against the fastest mind alive,” he said. “We’re also trying to lighten the tone this year. Last year was pretty dark, we’re going to try to get back to the jokes.”

Sawyer has most recently appeared in CW Seed’s “Saving the Human Race.”

“The Flash” Season 4 is set to premiere on the CW Oct. 10.