Dal (Echoes of War)

"Dal" was the name given to a Dalek suffering from amnesia after a serious accident (AUDIO: Echoes of War).

History
While the Doctor was attempting to rescue the survives of the luxury liner Theseus, a Dalek fleet forced the last of the Theseus survivors to crash-land on a jungle planet. Due to the scale of the damage inflicted in the crash, the Doctor was accompanied by only eleven human survivors, with one nearby Dalek. However, the Dalek had sustained so much damage that it was unable to recall its past or programming,

Faced with a prolonged journey to a temporal safe-zone he had detected with a makeshift scanner, the Doctor was able to convince the damaged Dalek that it was a friend of the survivors so that it would use its sensors to help them reach the safe zone, encouraging the Daleks' focus on its natural goal of survival to ensure that it would help them. After a near-slip by one of the other refugees, the Doctor told the Dalek that its name was 'Dal', introducing himself as 'John Smith' to prevent the Dalek regaining its memories of him. During the trip to the safe zone, the group witnessed flashes of a battle against the Daleks that would take place at some other time, but the Doctor claimed that the temporal anomalies had driven the rest of its race insane.

After the Doctor was separated from the rest of the refugees by a temporal anomaly, Bliss briefly suggested that Dal act as the group leader, but Dal retained enough of a Dalek respect for authority to defer to Bliss as she was the member of the group who had been closest to 'John Smith', whom it had already identified as the leader. As the group continued to advance, they discovered the TARDIS among the remains of the Theseus, with Dal insisting that the group bring it along by adapting some of the remains of the Theseus to enhance its own hover ability to encompass the TARDIS, despite the ship having sustained so much damage that its link to its internal dimensions had been damaged.

When the refugees were attacked by the local population of rapidly-evolved monkeys a short distance from the safe zone, Dal instinctively used its weapon against them, the subsequent return of the Doctor prompting more of Dal's memories to return. As the Doctor led the refugees to the safe zone, he attempted to convince Dal to run a systems reboot while remembering everything that Dal had experienced on their trip across the jungle planet, in the hope that this would encourage Dal to hold on to what it had become instead of reverting to traditional Dalek behavior. However, when the Doctor went back to talk to Dal, the Dalek was shot by a Time Lord platoon that had been sent to retrieve the Doctor before the Doctor could definitively learn whether his efforts to change Dal had been successful. (AUDIO: Echoes of War)