ThemoonrisesatapredestinedangleandawakensthesleepingDr.Phibesin1928,threeyearsaftertheeventsofthepreviousmovie.Tohisdismay,hefindsthathishousehasbeendemolishedandhispapyrusscrollsstolen,thescrollsheneedstofindthePharaoh'sTombinEgypt,wheretheRiverofLifeflows.Afteridentifyingthesourceofthepapyrustheft,hepacksandleavesforEgyptwithhisassistantVulnavia-whosefacedisplaysnoeffectsfromtheacidshowershereceivedattheendofthepreviousfilm(althoughthecharacterisnowplayedbyadifferentactress,ValliKemp).Hisprimarygoalistheawakeningofhisdeadwife,Victoria.
ThethievesofPhibes'scrollssufferanattritionproblemasInspectorsTroutandWaverlychasePhibesacrosstheworld.ThepartyisledbyBeiderbeck(RobertQuarry,bestknownforplayingCountYorga).Althoughhelooksyoung,heisseveralhundredyearsoldandwantstofindtheRiverofLifeinordertostayaliveandbewithhisloverDiana(FionaLewis)forever.ThistimePhibes'murdersallhaveanEgyptianthemetothem;forexample,onecharacterissand-blastedtodeath.Otherdeathsincludesomeonebeingstungtodeathbyscorpions,beingeatenbyaneagle(intheoriginalscriptimpaledbyagoldeagleinthesamewayadoctorinTheAbominableDr.Phibeswasimpaledbyagoldenunicorn),andagoldensnakepiercingsomeone'sskull.
Attheclimax,BeiderbecksacrificeshislifeinordertosaveDiana.ThefilmendswithPhibesridingaraftdowntheRiverofLifewithVictoria,whilesinging"OvertheRainbow"(whichisstrange,asthisfilmissetin1928but"OverTheRainbow"wasn'twrittenuntil1938).ItisleftambiguouswhetherVictoriaisresurrectedornot,althoughapictureinsidetheDVDshowsherintheraftwithhereyesopenandsmilingatthecamera