Though not as meaningful as it once was, hitting the 100 episode mark is still a pretty big deal. Some shows like to celebrate this achievement by staging big, narrative-altering moments. Others bring back former cast members to honor the past as they move forward to the future.

The Blacklist? It brought in Nathan Lane to battle James Spader's Red over a rare penny. And you know what? It was one of the more enjoyable episodes in recent Blacklist memory.

The show has long demonstrated an underrated ability to mix tones and genre conventions within its outwardly ridgid procedural structure. Skills of the various Blacklisters have verged on sci-fi territory, and Spader's perfectly big performance is strategically comedic when necessary. But "Abraham Stern" (of course #100 on the Blacklist) featured a supremely fun, mostly lighthearted showdown between Reddington and Lane's titular Stern -- again, mostly over one of the rare bronze Lincoln pennies.

Lane is an equally rangey actor, but when someone like him and Spader are in the same zip code, things are bound to go broad, in the best of ways. Here, Lane and Spader were able to exhibit palpable chemistry, first as rivals, then temporary partners, and then rivals once more.

Lane has an uncanny ability to play characters who so completely believe their own BS that it's almost impossible to be mad when they end up turning on allies. His Stern sold Red a story about promises to his dead father so effectively that Red couldn't help but go along with Stern's plan to rob the Denver Mint even though he knew it was sure to be a double-cross. Red wasn't even mad, he was just impressed.

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Lane and Stern tapped into a key to great Blacklist episodes: Red needs to be challenged. The show too often revels in his genius, to the detriment of the other regulars. But when there's a villain in the mix that can out-think and out-maneuver Red, both the story and Spader's performance have more energy.

Spader was particularly engaged in this one, turning in at least five of his best line readings in 100 episodes. The pure glee behind his explanations of the Lincoln penny and the supposed conspiracy behind the Federal Reserve's mysterious unmarked bills radiated through the screen. And his exclamatory "aha!" when his last-ditch attempt to steal all the unmarked cash from Stern, who was in the midst of stealing it from the Mint? True bliss.

To cap off the fun, Red's heist of the Mint -- what he called the heist of the 21st century -- enabled him to get the Lincoln penny back, which he then flipped for Winston Churchill's hat. Only a show this low-key weird, with a performance similarly charged, could conclude its 100th hour with the lead character excitedly explaining how he was "an unworthy heir" to wear an ugly hat.

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Spader doesn't deserve an Emmy for this work. It's something beyond that; he's in the kind of zone that only legends can reach, and shouts to his buddy Lane for bringing it out in him.

Speaking of weird, while Red was cosplaying National Treasure, Liz (Megan Boone) was forced to dig up old files on The Stewmaker in a nice shout out to Season 1 so that she could, you know, disintegrate a human body. Wherein she discovered a glass eye, complete with some kind of high-tech tracking device in it!

Again, this episode ended with a guy laughing about a hat. Look, you don't make it to 100 episodes by being completely boring.

The Blacklist aris Wednesday at 8/7c on NBC.

Other Links From The BlacklistJames SpaderMegan BooneNathan Lane