Warning: This article contains spoilers from "Westworld" through episode 3. Read at your own risk.

HBO's "Westworld" is full of familiar faces, from Anthony Hopkins to Thandie Newton to James Marsden. While he doesn't have the name recognition of some of his fellow cast members, Jimmi Simpson is certainly someone viewers should recognize thanks to his prolific work in TV series such as "House of Cards" and "It's Always Sunny in Philadelphia," as well movies such as "Zodiac" and "White House Down."

In...