You’ve been warned: There will be at least 5.5 hours of 2021 Oscars programming

Get the popcorn, Raisinets and massive fountain soda ready: The 2021 Oscars are going to be a long, long televised event.

ABC is running the table Sunday night, starting with “Oscars: Into the Spotlight,” a preshow that will include performances of the five tunes nominated for original song.

Celeste and Daniel Pemberton will perform “Hear My Voice” from “The Trial of the Chicago 7,” H.E.R. will sing “Fight for You” from “Judas and the Black Messiah,” Leslie Odom Jr. will perform “Speak Now” from “One Night in Miami …,” Laura Pausini and Dianne Warren will perform “Io Si (Seen)” from “The Life Ahead,” and Molly Sandén will perform “Húsavík” from “Eurovision Song Contest: The Story of Fire Saga.”

Then at 5 p.m. Pacific, live from L.A.’s Union Station and the Dolby Theatre in Hollywood, comes “The Oscars” ceremony itself — an affair that’s been known to run past its three-hour window. This year winners have been instructed to “read the room” and “tell a story” in their acceptance speeches, so who knows what will happen.

But as soon as that ends, folks who don’t change the channel can see “Oscars: After Dark.” Hosted by actors Colman Domingo (“Ma Rainey’s Black Bottom”) and Andrew Rannells (“The Prom”), it will close things out with a review of the night’s biggest moments and interviews conducted by film critic Elvis Mitchell.

For anyone doing the math, that’s at least 5.5 hours of Oscars programming in one night. “Zack Snyder’s Justice League,” at 4 hours and 2 minutes, looks positively svelte in comparison.

Times intern Angie Orellana Hernandez contributed to this report.