Esmeralda rescues Phoebus from where he lands in the river, unbeknownst to Frollo, and then hides him with Quasimodo in the bell-dower.
Esmeralda rescues Phoebus from where he lands in the river, unbeknownst to Frollo who wants to "let the traitor rot in his watery grave". Esmerelda then hides Phoebus with Quasimodo in the bell-dower.