Watch our a rare blue American Lobster (Homarus americanus) molting is this sped-up video. This blue lobster is only about one in about 5 million; a blue lobster is missing most of its red and yellow pigments.
When a lobster grows too big for its carapace, it struggles out of it. At the same time, its soft body absorbs water to expand its size. The soft body hardens to be come its new shell.