The 36-year-old Irish actor played the roles of Kíli in the three-part fantasy film The Hobbit and Ross Poldark in the BBC adaptation of The Poldark Novels by Winston Graham.
Stranger Things star Joe Keery, who plays Steve Harrington in the sci-fi series, will also join the line-up at Telford's International Centre in December.
He will appear on December 7 and 8, while Aidan will only be there on the Sunday.
Other guests include David Tennant, Matt Smith and Catherine Tate, from Doctor Who; Buffy The Vampire Slayer’s James Marsters and John Ross Bowie from The Big Bang Theory.
For the full line-up and information on how to get tickets visit walescomiccon.com