MD 135 turns southeast into Allegany County and enters the town of Luke as Pratt Street. The state highway immediately intersects Masteller Road, which is unsigned MD 135D and meets the eastern end of the western segment of West Virginia Route 46 (WV 46) at the North Branch Potomac River. At a bend in the river, MD 135 makes a sharp turn to the north around the mountain and the road passes the large NewPage Corporation paper mill. The state highway turns east and its name changes to Church Street upon entering Westernport, where the highway intersects MD 36 (New Georges Creek Road), which crosses the North Branch Potomac River to become the eastern segment of WV 46. MD 135 crosses Georges Creek and meets the Georges Creek Railway at-grade before intersecting Main Street, which is unsigned MD 937. Upon leaving Westernport, the road's name changes to McCoole–Westernport Road. MD 135 parallels the North Branch Potomac River and Georges Creek Railway as it passes scattered residences and businesses. Upon reaching McCoole, the highway passes unsigned MD 135A, which provides an alternate access route to US 220 north. Shortly after, MD 135 reaches Paxton Street, which is officially MD 135B but is marked as MD 135. Paxton Street leads to a junction with US 220 (McMullen Highway). MD 135 itself continues east under the McCoole–Keyser bridge to its eastern terminus at the intersection of Queens Point Road and Golden Cross Street.