Spikes of Doom

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The Spikes of Doom was a potential trap within Castle Tersurus which the Master had bribed the architect to make, having travelled back 100 years before he was to meet with the Ninth Doctor and his companion Emma there. The Doctor, however, had anticipated this and so travelled back to bribe the architect at an earlier point. As a result, rather than being subjected to the Spikes of Doom, the Doctor and Emma found themselves sat on the Sofa of Reasonable Comfort. (TV: The Curse of Fatal Death)