Malcolm, whose frenetic home life is a kind of zoo, begins the fourth season by accompanying his family to the real thing. A visit to the zoo offers close encounters with creatures great and small. But Hal wishes he could have passed on an encounter with Lois's former beau, who lectures on rain-forest animals. Elsewhere, Reese butts heads with a goat; and Malcolm and Dewey take a tumble into a tiger den. Another storyline checks in on ne'er-do-well Francis, now the unlikely foreman of a dude ranch owned by a cheery German businessman.