Cheryl's concern escalates over Seamus's disappearance. Can Brendan keep his terrible secret? Meanwhile, a harassed Joel deals Theresa heartbreaking news, but can she change his mind? Elsewhere, Mercedes manages to make inroads with Myra, but there's trouble ahead when Mercy jumps to the wrong conclusion. Also today, Bart fears that he'll never be able to turn over a new leaf. Finally, as Esther is pushed to the limit, she makes a decision that will affect all of the sixth formers.