A pebble and a riverbank are witnesses to the endless meetings of Mona, who came to forget Eko, and Eko, who after eighteen months away comes to make up with her. When she hurls a pebble into the water—a pebble suffused with her sorrow—Mona sends her friend into a time loop he alone knows about: a day without end that sees Mona tossing the pebble in and Eko doing everything he can to prevent her.
