Stargate SG-1
I can't remember anything so poignant on SG-1 as Sam doing the puzzle with youthful Orlin (

Cameron Bright) in the hospital (mental facility?). The poor sod sacrificed his memory to help curb the Ori plague, and for what? To end up in a rec room at Bellevue. My gut told me Orlin's fate would be sad, but the way it played out was especially moving. Indeed, the second half of the "Four Horseman" story arc was one of the best and most touching stories of the entire SG-1 saga. Everyone had a chance to shine in scenes of wit, courage and compassion. Not many actors can do righteousness as well as Louis Gossett Jr., but Christopher Judge comes close. Listening to Gerak and Teal'c roar imperiously at each other before the Jaffa council was a blast and a half. Come to think of it, Gerak was a blast  or rather, a burst when he erupted into flames for saving Landry and the other plague victims. But he died a free man, so nerts to you, Ori. The Mitchell-Jackson repartee at the expense of the captured Prior (Mitchell called him "a dark-side encyclopedia salesman") was terrific, and the cameo from Don S. Davis' General Hammond was another nice touch. However, Bright's performance as Orlin was the ace. A less-gifted actor would have turned the adolescent Ancient's subdued personality into something wooden or one-dimensional, but Bright communicated wisdom and loss beyond his years. Along with the equally terrific Amanda Tapping, the lad turned a great episode into a classic.