When you think of Dan Stevens, you probably think of Matthew Crawley, heir presumptive to the Grantham estate in the British TV series Downton Abbey: Polished, progressive, well-heeled, and devastatingly handsome. You probably don't think of suicidal wrecks nursing laudanum addictions, sex-shy nebbishes, haughty narcissists, schizophrenics with incalculable psionic powers, or unstoppable killing machines.