He returned to league football when signed by Hearts in April 1932 and had gradually worked his way into the first team by 1934, appearing mainly as a left-winger.
He switched to the right flank from 1934–35 and that season helped Hearts to the Scottish Cup semi-finals, playing in both games as Double-winning Rangers proved too strong in a replay at Hampden Park.
He went on to spend thirteen years with the Tangerines, making 136 league appearances and scoring seventeen goals for them.
This total would have been considerably greater but for the disruption of the Second World War, during which time he "guested" for Middlesbrough and Brighton and Hove Albion.
Munro won three caps for Scotland (the first two during his Hearts days; the other while with Blackpool) and scored one goal, against Ireland on 31 October 1936.