Silent (Revolution of the Daleks)
From Tardis Wiki, the free Doctor Who reference
A Silent was imprisoned in the Judoon prison where the Thirteenth Doctor was held during her sentence. She stated that she forgot they were here, before being interrupted by Captain Jack Harkness, forgetting it again. The Silent watched the Doctor and Jack escape through the cell walls, using Jack's breakout ball (TV: Revolution of the Daleks)
