weak link

But the adventurer did dare, and the loophole, the weak link, was exposed.

There must be not one weak link in his close-meshed chain of propositions.

Hit the source, the weak link, the roots of the poison tree.

She had been the weak link in his life, the life which he had so wanted to crown with success.

Nagel was the weak link in their armor—a threat to their safety.

But you don't know him, Stuart; that is the weak link in the chain.

In his carefully welded plot-chain, Ku Sui left one weak link, though he was not aware of it at the time.

The weak link in the chain of evidence against Lady Eileen Meredith was the lack of motive.

He may deny it if his conviction hangs upon that point Mr. McCausland wishes to leave no weak link in the chain.

The next day, however, the weak link stretched beyond its own line and essayed an assault on Cantigny.