恶第四季

　　1.BokoHaramUnnaturalSelection:TheNigeriangovernmentisdeterminedtodrivemilitantsfromaterroristgroupoutofthecountryAnewgene-editingmethodallowscientiststochangethegenetictraitsofplantsandanimals.
　　2.EscapetoEuropeCycleofTerror:FollowingtherefugeetrailfromtheSyrianbordertoEuropeTheglobalreactiontotheterroristattackinParisimpactsthefightagainstterrorism.
　　3.RighttoDie:Exploringthemoral,politicalandpersonalquestionsraisedbyeuthanasia.
　　4.BeatingBlindnessWhiteCollarWeed:DoctorsandresearchersmakeincrediblestridesinthefightagainstblindnessStrugglingsmall-scalemarijuanafarmersfacecorporatetakeoversastheendofthepot-prohibitionnears
　　5.MeathookedEndofWater:ExaminingtheenvironmentalharmofindustrialmeatoperationsAssessingthedepthsoftheworld'swatercrisis.
　　6.ReturntoYemenChurchandStates:ExaminingtheconflictinYemenExploringtheongoingbattleforLGBTequalrightsintheUnitedStates.
　　7.PalestineNowandVivaCubaLibre:ExploringthelivesofyoungPalestinianstodayExaminingthepoliticalthawingofrelationshipsbetweenCubaandtheUnitedStates.
　　8.AfghanWomen'sRightsFloatingArmories:ViolenceandoppressionarestillafactoflifeforwomeninAfghanistanPrivatemilitarycontractorsprotectglobalcommerce.
　　9.TheFutureofEnergy:Examiningthefutureofhowtomakeanduseenergyandhowtomeetthegrowingdemandascarbonemissionsarecut.
　　10.TrumpinDubaiChinainAfrica:TheplightofmigrantworkersinDubaiExaminingtheincreasinglyprominentbusinessrelationshipbetweenChinaandAfrica.
　　11.TheDealCityofLostChildren:ExploringtherecentIrandealfrombothsidesTribesofhomelesschildrenlivealongthetracksinKolkata,India.
　　12.TheEndofPolioandCollateralDamage:HealthworkersputtheirlivesonthelineinPakistantoeradicatepolioExaminingthedevastatingeffectsofunexplodedordnanceinMyanmarandLaos.
　　13.StateofSurveillance:ShanetravelstoMoscowtomeetwithEdwardSnowdenanddiscussgovernmentsurveillanceprograms.
　　14.HeroinCrisisNewAgeofNukes:TheeffectsofAmerica'sHeroinepidemicandthenextnucleararmsrace.
　　15.FlintWaterCrisisLibyaontheBrink:ExaminingtheeffectsofthewatercrisisinFlint,Mich.InLibya,rivalmilitiasfighttosavethecountry.
　　16.DieTrying:PatientsandtopresearchersacrosstheU.S.discussrecentmeasurestakentotackleALSExploringtheregulatoryhurdlesfacedbyALSpatientsanddrugmakers.
　　17.StudentDebtFecalMedicine:Thecorrelationbetweenstudent-loanborrowingandthesoaringcostofcollegetuitionAmedicalrevolutioninvolvesusingstoolfromahealthypersontotreatsevereintestinalinfectionsinothers.
　　18.TheNew$paceRaceClosingGitmo:NASAandagrowingcommunityofprivatecompaniesdecidetoprepareforMarsexplorationEx-detaineesrevealwhatreallyhappensbehindthewallsoftheAmericanprisonatGuantanamoBay,Cuba.