'The Flash' Season 2 Spoilers: 'Arrow' Season 4 Crossover Plot Revealed; John Diggle To Go Against King Shark In Episode 15

The most fun part of being a fan of either the CW’s “Arrow” or “The Flash” is being treated to the occasional crossover between the two super-powered teams. Now, after a series star teased his involvement with “The Flash” on social media, the plot of his trip to Central City has been revealed.

“Arrow” character John Diggle (David Ramsey) will take a vacation from fighting crime in his home town of Star City to help Barry Allen (Grant Gustin) take on a villain on behalf of the U.S. government. As previously reported, the actor essentially confirmed he’d have an appearance on “The Flash” later this year with a not-so-subtle post on Instagram. That photo left fans with the question of what exactly will bring the former U.S. soldier-turned vigilante on an adventure with Team Flash. According to news outlet ComicBook, he’ll actually be tagging along with his wife, Lyla (Audre Marie Anderson).

In previous episodes of “Arrow,” Diggle’s wife was revealed to still have ties to the fictional government organization known as A.R.G.U.S. (Advanced Research Group United Support). Showrunner Andrew Kreisberg told the outlet that Diggle will help Lyla track down a major threat that has escaped prison on episode 15 of “The Flash.” After King Shark (David Hayter) launched an unsuccessful attack on Team Flash, the speedster, and Harrison Wells (Tom Cavanagh), put him in jail. Unfortunately, it seems bars aren’t enough to contain the half-man/half-shark mutant, who escapes and returns to Central City to finish killing Allen.

As CinemaBlend notes, Diggle has appeared on “The Flash” in the past, most recently in the major crossover event during episode 8 of Season 2 and “Arrow” Season 4 respectively. However, this will be the character’s first time on a crossover adventure without The Green Arrow (Stephen Amell) or Felicity (Emily Bett Rickards) present to bridge the gap between the two shows.

King Shark’s first, and so far only, appearance on the show came as a surprise to many fans as the fully computer-generated character grabbed the Flash at the end of a previous episode and became one of the more outrageous-looking villains that the hero has been forced to battle (or in this case get beat up by). Unfortunately, nothing else is known about how the events of the upcoming crossover will shake out for Diggle, Lyla and the members of Team Flash. No date has been announced for the crossover event.