noun

reckless mischief; wild spirits.

his eyes were blazing with devilment

mischief,naughtiness,badness,bad behaviour,misbehaviour,mischievousness,troublemaking,misconduct,misdemeanour,perversity,disobedience,pranks,impishness,tricks,larks,capers,nonsense,roguery,rascality,devilry,funny business,diablerie,monkey business,shenanigans,goings-on,hanky-panky,carry-on,carryings-on,jiggery-pokery,monkey tricks