"Catalysts"
... that when actress Vanessa Marshall learned that she would be playing the character Mary-Jane Watson in the Spectacular Spider-Man episode "Catalysts", she dropped to her knees and began hyperventilating?
... that when actress <a href="./Vanessa_Marshall" id="mwE5I" rel="mw:WikiLink" title="Vanessa Marshall">Vanessa Marshall</a> learned that she would be playing the character <a class="mw-redirect" href="./Mary-Jane_Watson" id="mwE5M" rel="mw:WikiLink" title="Mary-Jane Watson">Mary-Jane Watson</a> in <i id="mwE5Q"><a href="./The_Spectacular_Spider-Man_(TV_series)" id="mwE5U" rel="mw:WikiLink" title="The Spectacular Spider-Man (TV series)">the Spectacular Spider-Man</a></i> episode <b id="mwE5Y">"<a href="./Catalysts_(The_Spectacular_Spider-Man)" id="mwE5c" rel="mw:WikiLink" title="Catalysts (The Spectacular Spider-Man)">Catalysts</a>"</b>, she dropped to her knees and began <a href="./Hyperventilation" id="mwE5g" rel="mw:WikiLink" title="Hyperventilation">hyperventilating</a>?