1. Jon Hamm Took Sarah Clarke ("24," "Twilight") to Prom at John Burroughs High School in St. Louis.
2. Hamm Later Returned to John Burroughs High as a Drama Teacher, Where One of His Students Was Ellie Kemper.
3. The Former Teacher and Pupil Would Eventually Star Together in "Bridesmaids."
4. Vincent Kartheiser and Alexis Bledel Got Engaged In March.
5. January Jones Was One of the American Girls Who Slept With Colin in "Love Actually."
6. Aaron Staton Won Critical Acclaim For Playing Cole Phelps in the 2011 Video Game "L.A. Noire."
7. Jessica Paré Thinks Boobs Are Funny
8. Glen Bishop, Sally Draper's Creepy Not-Boyfriend, is Played By Matthew Weiner's Son.
9. Alison Brie Was in an Episode of "Hannah Montana."
10. John Slattery's Current Wife, Talia Balsam, Plays Roger Sterling's Ex-Wife, Mona.
11. Christina Hendricks Appeared in Two Episodes of the Cult Sci-Fi Series "Firefly."
12. Christopher Stanley Played Minor Roles in Both "Argo" and "Zero Dark Thirty."
13. Like His City-Boy Character, Vincent Kartheiser Didn't Own A Car Until Very Recently.
14. Like Her French-Canadian Character, Jessica Pare Was Raised in Montreal and Has a College Professor For a Father.
15. The Newest Bobby Draper Played Teri Hatcher's Son on "Desperate Housewives."
16. Christina Hendricks and January Jones Both Made Their Acting Debuts in an Unaired MTV Pilot From 1999.
17. Robert Morse Won a Tony Award in 1990 For Starring in a One-Man Show About Truman Capote.
18. Jon Hamm's First Televised Role Was Billed: 'Gorgeous Guy at Bar,' in a 1997 Episode of "Ally McBeal."
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