Arrowverse fans will see a lot of Malcolm Merlyn after John Barrowman signed a deal that will allow him to appear in all CW superhero shows.

According to TVLine, Barrowman will appear on all superhero shows produced by Greg Berlanti, including "The Flash" and "Legends of Tomorrow," while he will also continue to maintain series regular status on "Arrow." The deal is similar to what Wentworth Miller, who was a mainstay on "Legends of Tomorrow," signed with the CW Network.

Berlanti explained in May that they really want to emulate the comic books, where there are really a cast of characters. He stated the hope that eventually all the other characters will find their way in the other shows.

Barrowman appeared as the main antagonist of "Arrow" Season 1 and was cast as a series regular in Season 3. As Malcolm Merlyn, Barrowman oscillated from all sides, sometimes being good and at times bad, depending on where his interests lie. He also made an appearance in "The Flash" in one of the crossover episodes.

According to Vine Report, the deal is groundbreaking as it casts Barrowman as a series regular for all Berlanti produced CW shows, which includes "Supergirl," which recently transferred to the CW network. While it is not clear yet if Barrowman will also be a series regular in "Supergirl," fans are looking forward to seeing how Malcolm Merlyn will fit into the storyline of the show, in case he is included as a series regular.

Expect Malcolm Meryln to spread villainy all over when the Arrowverse shows start airing in October.