Lair Of The Daleks was the fourth episode of the first series of Doctor Who Rebirth and is he first episode of Doctor Who Rebirth to feature the most dangerous enemy, The Daleks.
The Doctor and Ood Theta arrive on a prison ship high above Skaro and come across various species all locked away in cells which are being "farmed" to make a whole new sub-species of Dalek. This is also the only episode of Doctor Who Rebirth where a Dalek is a companion.