We all make connections between people. This person has acted with that person before, this director/actor will only work with that director/actor. Once I even made an entire spiderweb of hilarious links between all the previous Joker's and how their favorite movies tied them all together. But whether or not you have noticed this, The CW has chosen to cast large parts of their Arrow and The Flash team from within a select few well loved TV shows.
(For the sake of keeping this interesting, I won't include CSI since almost every TV actor has been in at least 1 CSI Episode.)
For me the connections started with the introduction of Manu Bennett as Slade Wilson (aka. Deathstroke) in Season 1 of The Arrow. I was pleased to see an actor I was familiar with and had previously enjoyed in Spartacus. Early the next season they introduce Cynthia Addai-Robinson, playing Amanda Waller; who had not only been in Spartacus as well, but was the partner of Manu Bennett's character Crixus, as Naevia.
Later that very same season in Arrow, Katrina Law joins the cast as Nyssa Al Ghul; and you guessed right, she's from Spartacus as well. She was the on-and-off lover of Spartacus and the one who taught Cynthia's character Naevia how to fight. Imagine that, Amanda Waller taking fighting lessons from Nyssa Al Ghul.
At around the same time in Season 3 of Arrow and Season 1 of The Flash, the two shows crossed over to take down the villain Captain Boomerang, played by Nick Tarabay, yet another main actor from Spartacus. As Ashur in Spartacus, he was the whipping boy of Manu Bennett's character Crixus who had attempted to take Naevia from him in revenge. Amusingly enough, Naevia is the one to end Ashur's life. I barely blinked when a few episodes later, who walks on to the screen in The Flash as Weather Wizard but Liam McIntyre, who played (Season 3's) Spartacus himself.
Is your mind spinning yet? So we have The two main characters in Spartacus playing two of the villains in Arrow and The Flash, their two love interests playing two strong female leads in The Arrow...and the man who played the anti-hero in Spartacus as Captain Boomerang, who will eventually end up in the suicide squad; amusingly enough to get an implant in his brain to be killed at the discretion of the same woman who'd removed his head before.
There was many a discussion to be had among our friends as to the similarities between not only the cast in the TV shows, but how parallel some of their roles and plot lines seemed to be. There had to be a common denominator between all of them though, since the only actor of the bunch that was native-born to the United States was Katrina Law.
That answer came to me when I was watching a Spartacus red carpet interview with Manu Bennett (serendipitous; after going down the rabbit hole of the internet reminiscing on the late Andy Whitfield, who was the original Spartacus). Apparently Manu Bennett had been surprised that he'd been called to be cast for Arrow to work with Stephen Amell, because Stephen Amell had gone to the casting for Spartacus. When Andy Whitfield passed away after season 1 of Spartacus, Stephen Amell had gotten a call to try out to fill the now empty spot in the TV show. The role went to Liam McIntyre, obviously, but HE was what connected them all. (Skip to 3:55 for talk on Arrow)
(On an aside: Jai Courtney, who played Varro in Spartacus, is taking the role of Captain Boomerang in the movie Suicide Squad; replacing his Spartacus cast-mate who also plays Captain Boomerang, in The CW's Arrow.)
Here, have a chart I made in Paint
The connections don't end there. The CW's Arrow and The Flash is literally "everyone and their cousin", since Firestorm from The Flash is played by Robbie Amell, Stephen Amell's cousin. This has to make you wonder just how much pull Stephen Amell has with the CW.
(At the request of people who are enjoying these connections and providing me with more, I will be adding to this list. You're all amazing!)
- David Ramsey (John Diggle, Arrow) and Tom Cavanagh (Dr Harrison Wells aka. The Reverse Flash, The Flash) are both from Blue Bloods.
- Wentworth Miller (Captain Cold, The Flash) and Dominic Purcell (Heatwave) played the two main characters in Prison Break, as well as partners in The Flash. Robert Knepper (Clock King, Arrow and The Flash) and Peter Stormare (Count Vertigo, Arrow) were also in Prison break with them.
- Clancy Brown (General Wade Eiling, The Flash) and Dr Martin Stein (The other half of Firestorm, The Flash) were in Sleepy Hollow.
- John Barrowman (Malcom Merlyn, Arrow), Alex Kingston (Dinah Lance, Arrow) and Arthur Darvill (Rip Hunter, Legends of Tomorrow) are from Dr. Who.
- Grant Gustin (Barry Allen, The Flash) and Nolan Funk (Cooper Seldon, Arrow) were both leaders of The Warblers on Glee.
- And hey since we went out there and brought Jai Courtney in from Suicide Squad, lets add another DC pair together; Colin Donnel (Tommy Merlin, Arrow) and Margot Robbie (Harley Quinn, Suicide Squad) acted in Pan Am.
What you choose to think about these connections is up to you, I just find it fascinating when a cast from one show beautifully transition into another.
(But then again, isn't that the point? Pre-established chemistry?)
And I did look up CSI, just for curiosity sake; pretty much everyone from The Flash and Arrow have been on Crime Scene Investigation, but apparently none have been together in one episode.