The “Once Upon a Time” Season 5 midseason finale will not be airing on ABC at 8 p.m. EST Sunday night. Episode 11 of the fairytale drama will be delayed due to President Barack Obama addressing the nation.

According to a press release from the White House, the president “will address the nation from the Oval Office about the steps our government is taking to fulfill his highest priority: Keeping the American people safe.” His speech comes on the heels of the attack in San Bernardino, California, where 14 people were killed and 21 wounded. Viewers can expect an update on the “ongoing investigation,” as well as the threat of terrorism.

The speech will air live at 8 p.m. EST on ABC, CBS, Fox and NBC. Obama’s address is expected to last approximately 15 minutes. TVLine reports that shows like ABC’s “Once Upon a Time” will be delayed 15 minutes. Other shows affected include Fox’s “The Simpsons” and “Brooklyn Nine-Nine,” along with CBS’ “60 Minutes” and NBC’s “Sunday Night Football.”

The delay will not affect the midseason finale of “Once Upon a Time.” Series co-creator Adam Horowitz took to Twitter to give fans an update.

As previously reported, episode 11 of “Once Upon a Time” will focus on the heroes of Storybrooke trying to stop Dark Hook (Colin O’Donoghue) and the rest of the Dark Ones from snuffing out the light. The situation looks grim – especially since the Dark Ones need to sacrifice someone.