Syfy has added several wrinkles to its annual “Twilight Zone” marathon.

It’s not only showing all 156 episodes of Rod Serling’s classic CBS series, in chronological order — “TZ” aired from 1959 to ’64 — but it’s airing them in HD. (That probably won’t make much of a difference for a black-and-white series from this era, but still . . .)

In honor of the 87-hour marathon — which concludes Sunday at noon — here are my Top 10 all-time favorite “Twilight Zone” episodes, in no particular order.

“A Game of Pool” (Originally aired Oct. 13, 1961)

This parable of life and death, decided in a seedy pool room (city unknown), features two actors with terrific chops and even better chemistry: Jack Klugman as Jesse Cardiff, the self-proclaimed best pool player on Randolph Street, and Jonathan Winters as the dead pool legend James Howard “Fats” Brown (“The best who ever was”). Fats materializes from pool-player heaven and challenges Jesse to a game. The stakes? If Jesse wins, he lives. If he loses, he dies. The banter between Klugman and Winters (stepping outside his comic comfort zone) is priceless. (And the timing was perfect: The episode aired shortly after the big-screen premiere of “The Hustler,” co-starring Jackie Gleason as pool legend Minnesota Fats.)

“The Monsters Are Due on Maple Street” (Originally aired March 4, 1960)

Suburban mob-mentality panic turns deadly when strange things begin to happen on Maple Street one summer night after something crashes nearby, cutting the power. Lights flicker on and off, cars start by themselves and, before too long, neighbor turns on neighbor when teenage Tommy suggests it’s the work of aliens from outer space.

“It’s a Good Life” (Originally aired Nov. 3, 1961)

This one still creeps me out. Evil youngster Anthony Fremont (Billy Mumy, later to star in “Lost in Space”) holds his family and small Ohio town hostage by killing anyone who doesn’t think good thoughts about him (or anything else) — turning them into something hideous before “wishing” them to a nearby cornfield. One of Anthony’s neighbors gets drunk at a birthday party and mouths off about the young lad. Bad move.

“Nightmare at 20,000 Feet” (Originally aired Oct. 11, 1963)

Bob Wilson (yes, it’s William Shatner) is flying home with his understanding wife after spending time in the loony bin following a previous mid-flight freakout. That’s why no one believes him when he — and only he — sees a huge furry gremlin trying to destroy the plane’s engines. Hey, it happens.

“The Fever” (Originally aired Jan. 29, 1960)

Fusty, uptight Franklin Gibbs (Everett Sloane) is in a Las Vegas casino after winning a trip to Sin City with his wife, Flora. He grudgingly drops a coin into a one-armed bandit and then becomes obsessed with the machine, which vocally beckons him (or is it just all that loose change?). A cautionary tale.

“Living Doll” (Originally aired Nov. 1, 1963)

Future “Kojak” star Telly Savalas (with hair, yet) is Erich Streator, a mean father who dumps his stepdaughter’s Talky Tina doll into the trash. Tina doesn’t like that — or Erich — and seeks her revenge. Not recommended for those with a fear of dolls (creepy or otherwise).

“Twenty Two” (Originally aired Feb. 10, 1961)

Liz Powell (Barbara Nichols) is a professional dancer who’s in the hospital, recovering from exhaustion. She has a horrific recurring dream in which she’s escorted to the hospital morgue — Room 22 — by a shadowy nurse in an elevator who repeats the same phrase: “Room for one more, honey.” So what happens when Liz is discharged from the hospital? I won’t spoil it for you.

“And When the Sky Was Opened” (Originally aired Dec. 11, 1959)

Three astronauts, just back from a space mission, vanish from existence — and from everyone’s consciousness — each time one of them checks out of the hospital. In the end, there’s no trace of them — or of their mission. Did they ever exist in the first place? Discuss amongst yourselves.

“Will the Real Martian Please Stand Up ?” (Originally aired May 26, 1961)

A busload of passengers are snowbound in a remote diner, unable to cross a bridge after something crash-lands nearby (echoes of our “Maple Street” friends). Suddenly all hell breaks loose: the jukebox plays itself, the lights flicker, the telephone rings and no one’s there. All the passengers know is that one of them didn’t board the bus.

“A Piano in the House” (Originally aired Feb. 16, 1962)

Acid-tongued, loveless drama critic Fitzgerald Fortune (Barry Morse, who later co-starred in “The Fugitive”) buys a player-piano as a birthday present for his kind, much-younger wife, whom he taunts mercilessly. The piano, it turns out, has a strange effect on Fitz’s dinner guests — who, trancelike, bare their souls every time the piano plays a different tune. Everyone but Fitz is horrified — until it’s his turn to reveal his true inner identity.