Arc continuation puzzle

In case anyone thinks continuations are straightforward, I've ported Eugene Kohlbecker's classic Scheme puzzle to Arc. What does (mondo-bizarro) print?
(def mondo-bizarro ()
  (let k (catch throw)
    (pr 1)
    (catch (k throw))
    (pr 2)
    (catch (k throw))
    (pr 3))
  nil)
Reference: ACM SIGPLAN Lisp Pointers, Volume 1, Issue 2 (June-July 1987) pp 22-28.