We use cookies
We use cookies to analyse traffic and personalise your experience. Non-essential cookies (analytics & advertising) are not set until you consent. Declining keeps the site fully functional. Cookie Policy
First Appearance · Marvel
First appeared in The Uncanny X-Men #221 · 1987
About the character
Nathaniel Essex — Mister Sinister — is a Victorian geneticist who made a deal with Apocalypse for immortality and became one of the X-Men's most calculating adversaries. First appeared in Uncanny X-Men #221.
What is a first appearance worth?
The Uncanny X-Men #221 has solid collector demand. A presentable raw copy in the UK typically attracts an offer in the low to mid three figures; high-grade or CGC-slabbed examples can push into four figures. Restored copies are worth less but still very much wanted — we buy across all grades and conditions.
Exact figures depend on grade and condition. See the full The Uncanny X-Men #221 valuation guide →
Selling your The Uncanny X-Men #221 — quick answers
Where did Mister Sinister first appear?
Mister Sinister first appeared in The Uncanny X-Men #221 (1987). Nathaniel Essex — Mister Sinister — is a Victorian geneticist who made a deal with Apocalypse for immortality and became one of the X-Men's most calculating adversaries. First …
How do I get a valuation for my copy of The Uncanny X-Men #221?
Send us a few photos (front cover, back cover, and spine) using our enquiry form. One of our specialist buyers will respond, usually the same working day, with a clear cash offer or any follow-up questions we need answered.
Do you buy first appearances in any condition?
Yes — we buy across the full condition spectrum from reading copies to CGC-certified slabs. The offer reflects the actual grade, and we will always explain our reasoning. There is no pressure and no obligation.
Selling your Mister Sinister first appearance?
Get my offer →
