Lex's secret experiment at LuthorCorp goes awry and causes a dangerous toxin to be released into Smallville. Those infected by the toxin, including Clark, Lana, Chloe, Lex, and Jason, imagine their greatest fears come true and then fall into a coma. Desperate to find a cure, Clark heats up the vials containing a cure while Lex is not looking. With the cure heated to the correct temperature, Lex does something unexpected with the unproven antidote.