Sentence:  In a happy moment for the Levy-Lawson-Levis, Lady Lytton was betrayed, seized, and <WSD>immured</WSD>. The Editor saw his chance, and made the Metropolis ring with the outrage. Levi was saved; so also was Lady Lytton. 
Meaning of the word marked with <WSD> tags:  To cloister, confine, imprison: to lock up behind walls.