Answer: underact

AnswerCrossword Clue
UNDERACTHardly emote
UNDERACTPerform with subtlety
UNDERACTPerform with restraint.
UNDERACTPlay with too great restraint.
UNDERACTPlay down, as a role
UNDERACTJust walk through a role, say
UNDERACTOpposite of ham
underactAct a part in a play or film in an overly restrained or unemotional way
underactto act subtly and with restraint