▁they ▁identify ▁by ▁them ▁drink ing ▁machine ▁oil . ▁They ▁attempt ▁to ▁amb ush ▁the ▁al iens , ▁and ▁during ▁the ▁sc uffle ▁one ▁of ▁al iens ▁is ▁d oused ▁in ▁water ▁from ▁an ▁aqu arium . ▁The ▁other ▁fle es ▁but ▁not ▁before ▁telling ▁the ▁g end arm es ▁to ▁stop ▁their ▁struggle . ▁The ▁chief , ▁who ▁regularly ▁d ines ▁at ▁the ▁restaurant , ▁arriv es ▁to ▁find ▁it ▁has ▁van ished ▁due ▁to ▁one ▁of ▁the ▁al iens ▁dis integr ating ▁it . ▁He ▁finds ▁the ▁al ien ▁who ▁was ▁d oused ▁in ▁water ▁walking ▁along ▁the ▁beach , ▁evidently ▁hurt . ▁As ▁he ▁follows ▁the ▁al ien , ▁it ▁falls ▁apart ▁and ▁col laps es , ▁reve aling ▁that ▁the ▁al iens ▁are ▁actually ▁rob ots ▁made ▁of ▁metal . ▁ ▁The ▁chief ▁brings ▁the ▁remains ▁of ▁the ▁robot ▁to ▁Cru ch ot ▁and ▁the ▁g end arm es ▁who ▁dedu ce ▁that ▁water ▁causes ▁the ▁met all ic ▁al iens ▁to ▁rust . ▁They ▁then ▁use ▁a ▁fire ▁tr uck ▁to ▁sp ray ▁the ▁citizens ▁of ▁Saint - T ro pez ▁with ▁water , ▁hoping ▁to ▁cause ▁damage ▁to ▁any ▁al iens ▁in ▁dis gu ise . ▁When ▁the ▁super visor ▁confront s ▁them ▁about ▁this , ▁they ▁reve al ▁the ▁al ien ' s ▁remains , ▁convin cing ▁the ▁super visor ▁of ▁the ▁threat . ▁ ▁The ▁g end arm es ▁build ▁a ▁rep lica ▁sau cer ▁to ▁b ait ▁out ▁the ▁al iens ▁and ▁place ▁it