Film and television career Rossiter soon established himself as a character actor in films and television, as well as on stage. He stated: "I think I sensed fairly early on that I was not physically or facially built in the way that would ever fit even remotely into heroic or what used to be called juvenile parts. I always played character parts – right from the start." His first film role was in A Kind of Loving (1962). In Billy Liar (1963) he played the title character's boss. His first major television role was as Detective-Inspector Bamber in the long-running police television series Z-Cars. He also had guest roles in series as diverse as The Avengers ("Dressed to Kill", 1963) and Steptoe and Son ("The Lead Man Cometh", 1964; "The Desperate Hours", 1972). Among his early film credits were four films directed by Bryan Forbes, namely King Rat (1965), The Wrong Box (1966), The Whisperers (1967), and Deadfall (1968).
filM and tElEvIsIon Career rossitEr Soon establiShed HimsElF as a CHAracTER acTOr IN FiLms and television, As WElL AS ON sTage. He STateD: "I tHink i SensEd fAIRlY eArlY on ThAt i was not pHYSIcalLY oR Facially BUiLt iN The Way THat Would eVER fiT evEN rEMOTELy intO HEroic or wHat uSeD To Be caLled juvEnile parTs i aLWays Playe.d CHAraCTer parts – righT From thE start." hIs fiRSt filM role WaS IN a KinD OF lOvIng (1962). in bILly lIAR (1963) hE PlayeD ThE tiTle chaRacTer's boSS. his fIRst mAJor TelevIsiON rolE was as DEtectivE-inSpeCtor bAMbeR in the LOnG-RUnNinG pOlice tEleVisIon series Z-cARs. hE aLso had GuESt RoLes in seRieS As diVErsE aS the avEngers ("dresSeD tO kill", 1963) ANd steptoe ANd SON ("the lead man comEtH", 1964; "ThE dEspeRatE hours", 1972). aMOnG his early film creDitS Were fOUr FIlMs DIreCtEd bY bryAN forbeS, NAmely kiNG raT (1965), tHE wrong bOx (1966), thE WhispeRErs (1967), aND DeadfAll (1968).