SessionAces.KeepersofTime.Vocalists.Composers.Thesidemenandsidewomenwhoplaytheriffsandfillsweimitateintheair.Whenweturnuptheradio,chancesarewearelisteningtooneoftheseplayers.A-listershavethemonspeeddial.Internationaltourorrecordingsession,who'retheygonnacall?A"HiredGun."Thisfeaturelengthone-offdocumentaryintroducestheprolificmusicianswhoarevirtuallyunknowntothepublic.BillyJoel,Whitesnake,P!NKandMetallicaaresynonymouswiththeirownartistryandsuccess,butwhoisresponsiblefortheirinstrumentalsolos?