Potential costumes for our main character

Our character as a doctor might wear:

• suit - as those who are high up in the business tend not to wear scrubs but their own work clothes and a suit is a typical work costume.
• scrubs - as he works in a hospital it may be that he has to wear scrubs if about to go into surgery, however it is unlikely that our doctor shall wear scrubs (as he isn't a surgeon or nurse). 
• white lab coat - doctors who are high up often wear a white lab coat to distinguish themselves from ordinary hospital visitors.

As a killer, our character may wear:

• a hoodie - as stereotypically killers are viewed as gangster who normally wear hoodies to hide their identity. Suggesting that there is something for them to hide.
• jeans - it is stereotypical for killers to dress plain, as they don't want to be pin-pointed as a killer/ stand out to the police.
• white t-shirt - again like the jeans it is stereotypical of a killer to wear something simple, to withdraw from standing out.