Plot hole - Caution: Here be spoilers
If Sir Robert was able to dig himself out so easily (right through the earth next to the blocked entrance to the foxhole) after cross-bowing Quive-Smith, why on earth did he not just do that before?
shareWhen the hole is blocked, Quive-Smith does warn Sir Robert that he and his henchman will be watching constantly in shifts to prevent him giving them the slip - he makes some sort of comment about his henchman being so nervous he may shoot him by accident if he tries to dig himself out. I assume that's why he didn't try it earlier.
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