A plank scaffold system and, more particularly, to a ladder-based vertically-adjustable plank scaffold system. The system may have a pair of ladders, a wall standoff mounted at the top of each of the ladders, a crane support mounted at the top of each of the ladders, a vertical guide bar and roller system to keep it from swinging on the cables, and a horizontal platform suspended on cables below the crane supports, the platform having a pair of cable winches mounted thereon for varying the elevation of the platform. Instead of ladders, tower scaffolds or stage towers may be used on each side to support the vertically-adjustable plank.