Johnny Galecki is a Belgian-born American actor, best known for his roles as David Healy in Roseanne, Rusty Griswold in National Lampoon's Christmas Vacation, and as Leonard Hofstadter in The Big Bang Theory.
as Mark(1 ep)
as Alex
as Self(1 ep)
as Self - Host
as Henry Montgomery
as David Healy(4 eps)
as Self - Host(8 eps)
as Paul Berger
as Gabriel
as Self - Guest(1 ep)
as Self(1 ep)
as Terry Ork
as Borel
as Self(1 ep)
as Self - Guest(1 ep)
as Self(1 ep)
as Ted
as Jeremy
as Leonard Hofstadter(279 eps)
as Self (archive footage)(1 ep)
as Scott(1 ep)
as Arnie (voice)(1 ep)
as Miles (uncredited)
as Self(1 ep)
as Leland Pressman(1 ep)
as Johnny Galecki(3 eps)
as Barry
as Jay(3 eps)
as Self(1 ep)
as Jude
as Peter Brown
as Darcy
as Seth
as Arthur
as Dale Stackhouse(2 eps)
as Leonard Hofstadter (voice)(1 ep)
as Knux (voice)(1 ep)
as Jason Bock
as Max Neurick
as Ira Reder
as Stingo Wheelie
as Teddy McNair
as Marty
as Daniel Hannigan
as David MacGregor(13 eps)
as Greg Stolbach(1 ep)
as Tim Seavers
as Eric
as Danny Nash(17 eps)
as Jason(1 ep)
as John Marshall(2 eps)
as Rusty Griswold
as Billy Quinn
as David Healy(92 eps)
as Toby Reardon
as Doug Rule
as Self(2 eps)
as Self - Presenter(1 ep)