Fourteen years is a long time to wait for a text message to arrive, especially when it's blank.
Mobile phone users in the UK are baffled after receiving empty text messages that appear to have been sent in the year 2003.
Reddit user Nihlus89 uploaded a screenshot of a text he was sent last week.
"Has this happened to anyone else? Should I be worried?"
Turns out they weren't alone, with dozens of others having taken to social media in recent months to report the creepy time-travelling texts.
"Just got a text from 2003, @VodafoneUK we can always rely on you for me to get my texts on time," wrote Twitter user @gracepearson_.
"Received a text today from 2003, how is that even possible? I was 6," wrote @HannahLittler1.
Regardless of when they were actually sent, the earliest of the messages appears to have arrived in October 2016.
But don't assume Back to the Future's Marty McFly or one of the "unstuck in time" characters from Lost is behind the mystery. Initial speculation on the source was that a glitch in one of the UK carrier's systems was to blame, but tech site TheNextWeb says it could be hackers taking advantage of a little-known mode in the SMS system called Protocol Data Unit, or PDU.
"Using PDU makes it possible to fake absolutely everything about an SMS, including the contents of the text as well as the sender details. All it takes to pull this off is a little technical mojo and a GSM modem to send out the messages.
"As a matter of fact, attackers have long relied on exploiting PDU to remotely infiltrate the devices of unsuspecting victims."
Cyber security experts say it's entirely possible scammers are to blame.
"I can confirm with 100 percent certainty that PDU mode can let you spoof anything," Nikolai Hampton told ScienceAlert.
"Would you like a message from your mother to remind you to get milk? Give me your number I'll send it to you."
The advice to users is to delete the messages, and report them to their mobile carrier.
Text messaging was perhaps at its height in 2003, before smartphones and data plans made using internet-based services like Whatsapp and Facebook Messenger more cost-effective.
If they are in fact messages sent by time travellers, it does beg the question why they'd use such an antiquated system like SMS.