This story contains no plot spoilers.

Series four of the BBC's "Sherlock" opens with the iconic detective Sherlock Holmes, played by Benedict Cumberbatch, in his usual comfy chair at 221B Baker Street. On his lap is a MacBook Pro and in his hand an iPhone 6S Plus.

This isn't the first time Holmes has used an iPhone or a Mac on the show, but nevertheless, this first scene pulled me out of the story before I could even get into it. Sherlock has an iPhone 6S Plus? Um, no. There's no way the great detective Sherlock Holmes would ever own an iPhone.

Josh Miller/CNET

What makes Sherlock Sherlock through every iteration on TV, film and in Sir Arthur Conan Doyle's original books is his independence from the herd. Sherlock's frenetic and dizzying mind, his insistence on thinking outside of the box and his often antisocial behavior all give him his extraordinary ability to solve crimes.

So why give him an iPhone, one of the most mainstream and recognizable phones you can find? Would a self-described highly functioning sociopath actually use the same phone as almost half of the UK and America? Wouldn't he want something more unique and specialized, or at least some tech as individual as he is?

If it's mere product placement, the show could have been a bit more clever about it. But giving the producers the benefit of the doubt, I thought through some possibilities that would help justify this bizarre ownership.

BBC One

The mystery of the "cool" iPhone

Let's run with the idea that Sherlock has on iPhone on purpose. The question is why.

Possibility 1: Maybe Sherlock wants to be cool. Though his intelligence and deductions are infallible, he can be quite vain.

Here's a snippet:

John Watson: You being all mysterious with your cheekbones and turning your coat collar up so you look cool.

Sherlock: I don't do that.

Watson: Yeah, you do.

Perhaps Sherlock has an iPhone to try to fit in?

Possibility 2: Maybe Sherlock's iPhone came as a free upgrade on a family carrier plan that he shares with his brother Mycroft, or perhaps with Watson and his landlady? Is it possible that Sherlock could ease his usually meticulous analysis in favor of financial convenience?

Possibility 3: A phone is a disposable tool for someone like Sherlock, who uses it for simple communication and research to augment the workings of his enigmatic mind. He can get what he needs done on any phone, and an iPhone is just as good as anything else. Plus it's easy enough to fix at the Apple store if it breaks during any of his hijinks.

(That said, can you imagine Sherlock going to an Apple Store to buy an iPhone? It would be like James Bond filling out paperwork for a rental car -- just ridiculous.)

BBC One

Sherlock is a Mac and Watson is a PC

Ok, so that might help explain Sherlock's iPhone in his lap, but what about his Mac laptop? Being loyal to a brand -- Apple or otherwise -- feels extremely out-of-character for the master of deduction.

This is where I think the dynamic between Sherlock Holmes and his assistant, Dr. John Watson, could come into play. Holmes and Watson have always had an unequal relationship, with Watson acting the straight-man foil to Holmes' out-there personality. Holmes still sees himself as Watson's superior, but Watson's presence helps ground him.

Molly: Don't you get John [Watson]'s texts?

Sherlock: No. I delete his texts. I delete any texts that begin "Hi."

This could also tie into their tech. In earlier seasons, Sherlock and Watson had a bit of a Mac-versus-PC quality to their friendship. Watson had a Mac computer and a Nokia phone while Sherlock had a PC and a BlackBerry. But by season four, things flipped. Sherlock now solves crimes from his iPhone and MacBook Pro. Watson documents their adventures on a Microsoft Surface Pro.

And -- still assuming the producers thought this through and we aren't just seeing this tech as a result of product placement -- here's where I start to change my mind about iSherlock: What if Sherlock's iPhone choice is a symbol of his character's growing status?

BBC One

As his friendship with Watson grows over the course of the show, their roles in that relationship change. By season four, Sherlock has become a full-fledged mainstream celebrity and his use of Apple devices now reflects that shiny conventionality.

Meanwhile, Watson's character is now emotionally strained. He has withdrawn from the societal ideals he has so desperately sought. Maybe Watson no longer wants a "cool," cultish laptop. He has a less flashy (but still powerful) Surface Pro and a somber, black-cased Android phone instead.

This could work.

Greater than tech

At the end of the day, I have to fool myself into accepting that Sherlock Holmes uses an iPhone rather than a niche phone with extra layers of security or something he's rooted and customized -- which you can do with Android, but not iOS.

Here's some proof he cares about phone security:

Sherlock, returning a character's phone: Oh, I sent and deleted a text. You might get a reply, but I doubt it.

Culverton Smith: It's password-protected!

Sherlock, sarcastically: Please.

The Sherlock Holmes of my head -- whether played by Cumberbatch, Jonny Lee Miller on CBS' "Elementary" (CBS is CNET's parent company, by the way), Robert Downey Jr. in the upcoming third "Sherlock Holmes" movie or Will Ferrell in an upcoming film comedy with John C. Reilly as Watson -- would still sport a phone more unique than an iPhone.

And either way, whichever phone he chose would still just be a tool. Ultimately, Sherlock's character and adventures are bigger than his phone and laptop and all his other tech combined. His brilliance through the ages rests on his most powerful personal computing device of all: the one under that deerstalker cap.

Tech changes over time, and Sherlock Holmes, a character who's been around for 130 years, will change with it. Maybe next season Cumberbatch's Holmes will see the error of his way and put aside that iPhone for good.

The violin, on the other hand? That stays.