Julian Cumberwhine is a Whitechapel lieutenant of Jack the Ripper. You find him at the gang meeting in the Jack's Lieutenants (Whitechapel) activity, which Arthur Weaversbrook asks Evie to break up in November 1888.
The activity sends Evie after five gang veterans at once. Hitting them from rooftops and ledges fulfils the optional objective of five aerial takedowns.
Cumberwhine is the first name on the list of five lieutenants Evie kills at the meeting.
Aubrey King
Aubrey King is a lieutenant of Jack the Ripper operating in Whitechapel. He is one of the five targets at the gang meeting in Jack's Lieutenants (Whitechapel).
Bruce Labott
Bruce Labott is one of the Whitechapel crooks who answer to Jack the Ripper. He appears as a target in Jack's Lieutenants (Whitechapel), the second of the expansion's lieutenant hits.
Cedric Barkers
Cedric Barkers is one of Jack the Ripper's lieutenants in Whitechapel and a target in the Jack's Lieutenants (Whitechapel) activity of the 1888 expansion.
David Roaming
David Roaming is a lieutenant of Jack the Ripper working in Whitechapel, and one of the men you remove in the Jack's Lieutenants (Whitechapel) activity.