Stephen Amell

'Brady' in The Vampire Diaries

'Jason' in Hung

'Scott Becker' in Private Practice

'G109' in Code 8

'Casey Jones' in Teenage Mutant Ninja Turtles: Out of the Shadows

'Oliver Queen / Green Arrow' in Arrow, The Flash, Supergirl, Legends of Tomorrow

'Jack Spade' in Heels

Willa Holland

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'Thea Queen' in Arrow

'Agnes Andrews' in Gossip Girl

'Audrey Anderson' in Legion

'Kaitlin Cooper' in The O.C.

Robert Knepper

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'Samuel Sullivan' in Heroes

'Tommy Dolan' in Carnivale

'Theodore "T-Bag" Bagwell in Prison Break

'Detective Rex Coughlin' in Hawaii Five-0

'William Tockman / Clock King' in The Flash and Arrow

'Antonius' in The Hunger Games

'Sid Rothman' in Mob City

'The Courier' in The Blacklist

'Simeon' in Stargate Universe 

'Keith Reynolds' in E.R.

'Deputy Carlyle' in Young Guns 2

Katee Sackhoff

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- 'Kara "Starbuck" Thrace' in Battlestar Galactica
- 'Dana Walsh' in 24
'Bo-Katan' in Star Wars: The Clone Wars and Star Wars: Rebels
'Dahl' in Riddick
'Sarah Hall' (voice) in Call of Duty: Black Ops 3
'Vic Moretti' in Longmire
'Amunet Black / Blacksmith' in The Flash

Greg Grunberg

(Yes that is Andre Royo in the foreground - if only I'd seen The Wire at this point in my life! )

'Carter Abbey' in Hollow Man
'Eric Weiss' in Alias
'Seth Norris / Pilot' in Lost
'Matt Parkman' in Heroes and Heroes Reborn
'Hugo Moller' (voice) in L.A. Noire
'Snap Wexley' in Star Wars: The Force awakens 
'Jeff Morrison' in Hawaii Five-0
'Commander Finnegan' in Star Trek Beyond
'Detective Tom Patterson' in The Flash

John Barrowman

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'Captain Jack Harkness' in Doctor Who and Torchwood
'Patrick Logan' in Desperate Housewives
'Malcolm Merlyn' in Arrow and The Flash  and Legends of Tomorrow
'Jeremy' in Zero Dark Thirty

Ah, the colour cast of Earl's Court. Correcting it seems to make his t-shirt wrong so this is the best I can get. The funny face he's pulling in the last picture is in response to my question ('What's your favourite scene you've been in, in Dr Who?). His initial reply was that anything with guns, explosions and big boys toys, but after I said that mine was the Trinny & Susannah-bot scene he laughed and said that really his was too but he didn't want to come across as vain...

(In case there's anyone reading this who doesn't know, the Trinny&Susannah-bot scene...well, he wasn't entirely dressed for all of it).