Could the Daleks be returning to Doctor Who for the 2019 New Year's Day special? It's a right of passage for every Doctor to take on the Time Lords' most feared foes, and the January 1 episode may be Jodie Whittaker's turn.
Whittaker's first season of Doctor Who has proven divisive among fans for various reasons, although one of the biggest has been its villains. New showrunner Chris Chibnall decided to avoid bringing back any previous monsters from either the classic or rebooted series in favor of antagonists that represent flaws in the human condition. While that made for some meaty stories, it meant not Sontarans, not Slitheen, no Cybermen and no Daleks. Eventually, though, the mutated Kaleds will have to appear, and it may be sooner than expected.
The Doctor Who New Year's Day special, "Resolution", will see the Doctor back fighting ancient evils on Earth. The official synopsis teases "a terrifying evil is stirring, from across the centuries of Earth's history". While that's not necessarily anything startling, the trailer suggests that terrifying evil is something the Doctor knows of already. She says the episode's villain is "the most dangerous creature in the universe", and the brief footage makes a big deal of hiding any hint at its identity or shape; it even ends on Graham asking "does it have a name?", teasing a big reveal.
That's all rather circumstantial as it is, but the obvious candidate out of Doctor Who's eclectic rogues gallery is undoubtedly a Dalek. The only other creature that comes close to that level of fear is the Doctor (see: "The Pandorica Opens", where an alliance of villains conspired to trap the Time Lord), and obviously she isn't talking about herself. A Dalek would also fit the explosive destruction shown and definitely warrant a big name reveal.
This does assume that "Resolution" features an existing creature; Chibnall may choose to maintain his rule of no returning monsters until season 12. The chrome-domes are terrifying for their inhumanity but had, admittedly, become far too defeatable monsters-of-the-week by the end of Steven Moffat's run (Peter Capaldi's regeneration episode saw the return of good Dalek Rusty, hammering home their neutralization). Now, though, we've had ten episodes of minimal canon connections; that's more than enough time to bring them back.
A Doctor Who festive special would definitely be a good way to introduce the Daleks to the Thirteenth Doctor's tenure. These episodes are typically watched by a much broader audience than season episodes of Doctor Who, and so having her most iconic enemy is a great way to ensure a crowdpleaser. The truth will come out in the haze of New Year's Day (unless Doctor Who marketing gives up the big secret early).