Leon Perkins

Doctor Leon Perkins was a human physicist.

He and Dr Irene Schulz travelled in time using a vortex manipulator.

Together they were tasked with procuring a painting from 1899. By mistake they travelled to 1999 and took a painting from a small museum, bringing it back to their client in exchange for a shot for Dr Schulz.

In 3912, the Thirteenth Doctor, Yasmin Khan, Graham O'Brien and Ryan Sinclair saw his hand sticking out from a portal because his vortex manipulator was sabotaged, and he was caught in a time loop. The Doctor calculated the space-time coordinates he would pop out next, and there Ryan and Yasmin pulled him out.

Perkins was then taken prisoner by the Grand Army of the Just, along with the Doctor and her friends. Once they had escaped, Perkins drew out a gun, and insisted that he needed to take the Doctor's TARDIS. (COMIC: A New Beginning)