Roots: Whatever Happened to Baby Jane? Romeo and Juliet II, ii (A rose by any other name...)
Dialogue Triumphs: "You are a free agent?" "-as free as I can be"
"Time can do anything it pleases given the right encouragement."
Continuity: Marshal Princess Louisa Keldafrian is joint commander-in-chief of the Imperial Keldafrian army and a veteran of nearly 50 campaigns across the Outer Reaches. The Keldafrians have limited space travel; among their hand armaments are proton knives.
Keldafria's enemies the Spiders are not actual arachnids but physical manifestations of the nerve endings of a greater creature, a being of pan-dimensional size and intellect with the ability to manipulate time (i.e. suspend its flow and create chaotic loops) and see into the future. To prevent the soldiers destroying the nerve endings the creature has woven a temporal and dimensional cocoon to entrap the sisters and their armies. The Doctor's arrival with Decay in his wake has fractured the cocoon. A chaotic time loop resembles a glowing spiral or spider's web on the TARDIS scanner.
Blood flowers are the royal emblem of Louisa's house. They resemble roses and grow on the plains of Keldafria where Louisa's armies had cut down the Spiders. The flowers are infused with the life fluids of the Spiders' pan-dimensional parent being and, as they are still connected to its central nervous system, touching them affects control of the time loop it has created. The Spiders don't believe in capital punishment, believing instead that if their aggressors were left in a time loop, they would effect their own destruction.
As intimated in other stories, anything within the TARDIS is essentially removed from existence. It shakes during a fold in time, and even its interior may not be safe. The dimensional shell of the TARDIS is being breached and the interior is suddenly filled with the huge spiders. The TARDIS was drawn into the time loop and it's the Doctor's presence here along with the TARDIS (which still has residual Decay in its telepathic circuits - see Links) that's disrupting the Spiders' loop and causing it to collapse.
The Doctor is aware when things are out of sequence around him. He is a good dancer (or at least a fast learner).
Location: The planet Keldafria, New Year's Eve
Links: This story immediately follows The Death Collectors
The Bottom Line: "We're all captives of our own conscience"
A simple tale told in a complicated way and for that a worthwhile experiment. As 'Henry' the sentient pan-dimensional being Kevin McNally is virtually unrecognisable - yet again featuring in a story with troublesome siblings.