Lost scenes of "Metropolis" rediscovered
zeit.de
zeit.de
Edit: not Lorre's screen debut, but his second appearance, as I just found out from this superb piece: http://www.logosjournal.com/issue_4.4/leming_printable.htm.
Guess they'll be yet another definitive final completely restored digitally enhanced version.
(Not that I mind; it's perhaps my favorite film.)