An above average American actor whose highest level of medical training was playing the role of a car salesman whose brother was autistic (Rain Man).
Also: Trained to prescribe drugs (primarily ALCOHOL) preparing for his role as a bartender in "Cocktail", maybe toxic viral agents since he played a minor role in MI2.
Random Guy:"Dude! I got me a banging hangover from those shots last night"
Tom Cruise:"Headaches don't exist, drink this sissy umbrella coctail and hold me!"
Random Guy:"Ouch! Did you just stick me in the ass with a needle?"
Tom Cruise:"Don't ask and I won't tell"