The mind-trip episodes of "Alias" have been among the strongest of the show so far: season 3 had "Conscious", season 4 had "In Dreams", and season 5 has "The Horizon". One thing they all have in common is how they surreally blur the line between dreams and memories: Sydney and Sloane do not just remember things as they happened; they change them in their minds according to their wishes - or their fears. These episodes are mind-bending in the same way that "Lost" at its best is ("Flashes Before Your Eyes"). But that's not the only strength of "The Horizon": we also get to see Peyton and Renée at their deadliest, Jack going all "Reservoir Dogs" on the captive Dr. Desantis to get him to reveal the location of the abducted Sydney (his answer is a cryptic clue: "it doesn't matter where she is, it matters where she's going"), the mythology of the show circling back on itself by using SD-6 as a major piece of the current puzzle, and a jaw-dropping revelation that the episode goes out of its way not to spoil by not announcing all the guest stars in the opening credits. The Sydney-Vaughn pairing rarely convinced me more than it does here. ***1/2 out of 4.
Review of The Horizon
