Did you spot the actress from Watchmen that guest starred on Smallville this past Thursday? I did.
Heroes - "Shades of Gray"
John Glover guest starred as 'Samson Gray,' Sylar's father. Previously, he starred on Smallville as Lex Luthor's father.
Castle - "Flowers For Your Grave"
Dan Castellaneta guest starred as 'Judge Markway.' His face may not be that familiar, but his voice is because he's usually Homer Simpson.
Lie To Me - "Do No Harm"
Mahershalalhashbaz Ali guest starred as 'Detective Don Hughes.' He used to appear star on The 4400 as 'Richard Tyler,' and he recently appeared in The Curious Case of Benjamin Button as 'Tizzy.'
Life - "Shelf Life"
Valarie Rae Miller, who guest starred as 'Erin Cordet,' was previously seen as 'Josie,' Sock's ex-girlfriend, on season 1 of Reaper.
Criminal Minds - "Demonology"
James Remar guest starred as 'Tom Benton.' He regularly plays the role of 'Harry Morgan' on Dexter and recently played a small role in The Unborn.
Bruce Davison guest starred as 'Father Davison.' He's very recognizable for playing 'Senator Kelly' in the X-Men films, and he also recently played the role of 'Charles Graiman' in the short-lived Knight Rider series.
Smallville - "Infamous"
Laura Mennell guest stars as 'Nurse Toni' who catches Davis in the hospital medicine closet. If she looks familiar, it's because you recently saw Watchmen, where she played the role of 'Janey Slater.'
Supernatural - "Death Takes a Holiday"
Christopher Heyerdahl guest starred as the demon 'Alastair.' He's also appeared on SciFi's Sanctuary as 'John Druitt/Jack the Ripper' and in season 7 of Smallville as Supergirl's father 'Zor-El.'