Will it be a trick for Cisco or a treat when Danny Trejo visits The Flash (sans machete, we presume) on Halloween night? The Flash Season 4 Photos

In a fresh batch of photographs from the brilliantly titled Season 4 episode “Elongated Journey Into Night” (airing Tuesday, Oct. 31 on The CW), we spy the cult film tough playing Gypsy’s father, Breacher, whose unexpected visit to Earth-1 catches Cisco off guard. Even more so when Breacher takes a disliking to Cisco and decides to hunt him!

Elsewhere in the Tom Cavanagh-directed episode, Barry runs into Ralph Dibny (guest star Hartley Sawyer), who is described as an “old nemesis” and who of course is fated to be the super-elastic Elongated Man. (Dibny was referenced in the Season 1 episode “Power Outage” as one of 14 people presumed dead in the S.T.A.R. Labs particle accelerator explosion.)

Check out all the new photos here.

Want more scoop on The Flash, or for any other show? Email InsideLine@tvline.com and your question may be answered via Matt’s Inside Line.