10 Deadliest Alien Prisons In Doctor Who

Another Time Lord device; the Genesis Ark was a Time War prison ship which used 'bigger on the inside' technology to store millions of Daleks.

Originally thought to have been lost in the Void during the Time War, the dimensionally transcendental prison resurfaced in 2006's Army of Ghosts/Doomsday to release an army of Daleks onto Earth. Protected within a Void Ship which had survived in the empty space between universes, the Genesis Ark was part of the Cult of Skaro's plan to reignite the Time War and conquer the universe.

Requiring the genetic imprint of a time traveller, the Cult of Skaro attempted to force Rose Tyler to open the Ark. Instead, they were interrupted by an attack by the Cybermen led by the Tenth Doctor. In the firefight, fellow time traveller Mickey Smith accidentally touched the Ark's casing, allowing its prisoners to break free.

Claiming that the Daleks would have blown up the sun to open the Ark if Mickey hadn't touched it, the Doctor set his sights on sending it back into the Void. As Daleks rained down from the sky above London and warred with the invading Cybermen, the Doctor concocted a plan.

Reopening the Void above Canary Wharf, the Genesis Ark, Daleks, and Cybermen were sucked back through. Because Rose Tyler had passed through the Void previously, she too was dragged towards the breach. With the Doctor powerless to save her, she became trapped in a parallel world before the Void closed itself.

Fearing entrapment in the Void, the Cult of Skaro performed an emergency temporal shift and evaded capture. Trapped forever, the Genesis Ark and its prisoners would now be lost in the ultimate prison - what the Doctor referred to as 'Hell' itself.

Intergalactic Travel Advice: Technically shouldn't exist.