Why is act 2 called the rising action? Discuss the complications in the conflicts that are in this act, and think about what might happen in act 3.

In The Tempest, act 2 is called the rising action because it builds up to the climax in act 3, scene 3 (where Antonio, Alonso, and Sebastian are attending Ariel's banquet). Act 2 includes complications that provide suspense and tension as the plot builds towards the climax, when the three guilty men must account for their past actions.
In act 2, Shakespeare introduces two main alliances: one that is a threat to Prospero and the other a threat to king Alonso. The rising action is usually filled with suspense, and Shakespeare certainly comes through in act 2. Here, the two alliances lead us to question whether Prospero will be successful in his avenging mission, as the action builds toward the climax. The first alliance is the one hatched between Antonio and Sebastian. Here, we must remember that this is the same Antonio who conspired with Alonso to steal Prospero's dukedom years ago.
In act 2, scene 1, the malevolent Antonio convinces Sebastian to kill Alonso (Sebastian's brother). With Alonso's son, Ferdinand, supposedly lost at sea and his daughter, Claribel, in faraway Tunis, Sebastian is closest in line to the throne. Sebastian agrees to kill Gonzalo (a good servant of the king), while Antonio will be the one to slay king Alonso. Their plans are stymied, however, when Ariel arrives to wake Gonzalo up. Antonio's and Sebastian's hands are stayed for now.
The other alliance of interest is that between Caliban, Stephano (the king's butler), and Trinculo (the king's jester). In act 2, scene 2, the three begin to form the beginnings of a terrible alliance; this partnership is not solidified, however, until act 3, scene 2, when Trinculo and Stephano promise to help Caliban kill Prospero.
In act 2, we see complications developing in Prospero's original plan for revenge. Prospero must contend with the rising threat of Trinculo, Caliban, and Stephano. At the same time, he must see to it that Sebastian and Antonio do not kill off Alonso before he (Prospero) has a chance to exact his revenge on Alonso.
These complications culminate in the climactic scenes of act 3, scene 3. The most important scene is where Ariel presents a bountiful spread before King Alonso and his royal court, only to withdraw it when everyone reaches for the food. In a solemn announcement, Ariel proclaims that Antonio, Sebastian, and Alonso must repent for their past acts of evil against Prospero. We suspect that the guilty parties will have to account for their past actions here, but the climax does not prove conclusive. The one thing it does do, however, is establish the fact that Prospero's enemies are now under his complete control.
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