Related Clues:

• Glass ceiling in block
• A stumbling block with first barrel - there's no head on the porter
• Advocate getting shot of street obstacle
• Brexit negotiator swaps note with Republican fence
• Block playwright meeting queen
• Fence? Cross-country runner needs new start
• Black bird removing hard obstacle
• Playwright sitting on top of retaining wall
• Scottish author with the ultimate in writer's block?
• Something that obstructs black bird, cutting head
• Scottish writer given right to build obstacle
• Wall, partition