Brief History

First appearing in Excalibur #6, "Professor" Alistaire Stuart is a member of the group MI:13, which is an intelligence group based solely in Britain. Other members are Captain Britain, Pete Wisdom, and so on and so forth. He and his sister, Alysande Stuart, helped fight off Warwolves a number of times. 
 Alistaire is a member of W.H.O. "Weird Happenings Organization" alongside his sister Alysande. In his first appearance, he introduces himself as Dr Alistaire Stuart, the resident science member of W.H.O. whilst investigating a locomotive which appears to be from an alternative reality where the third reich won the war.  
He next appears in issue 9, discussing the possibility of alternate dimensions alongside Commander Thomas who is very pessimistic about the concept when they are interrupted by five alien like creatures. Shortly afterwards, they're interrupted by Hauptmann Englande who attacks Commander Thomas. Alistaire appears to be very quirky and doesn't appear phased by what's happening but rather fascinated. Kitty Pryde and Rachel Summers come to the rescue creating more fascination for Alistaire.  

During Excaliburs battle with their  Nazi counterparts, Alistaire attempts to aid a downed Kitty Pryde where she quickly develops a crush on the quirky scientist. This also happens to be their first meeting with Widget who creates a portal that Alistaire quickly confronts out of curiousity against Kitty's protests. When an amazon attempts to pull Alistaire through the portal, Kitty phases through widget disrupting the portal. When Alistaire accompanys Kitty back to the others, he attempts to restrain her when she heads off to confront her nazi counterpart  but fails; only for Rachel to fly Kitty out of the window. Leaving Alistaire to remark, "Phoenix! A name -- and woman -- to conjure with. And risk everything to win!"