Home Alone fans are just realising who plays police officer at beginning of the film

Home Alone fans have been left shocked after only just realising who the cop is at the beginning of the movie.

For those of you who haven't given it a re–watch this Christmas, during the opening scene of the flick we see a police officer visit the McCallisters’ home as the family get ready for their trip to Paris.

The cop then talks to patriarch Peter McCallister (played by John Heard) who lets him know about all the security measures he’s put in place ahead of their trip, in the wake of a spate of burglaries in the area.

But as it turns out, the entire family end up jetting off to France and completely forget about eight-year-old Kevin (played by Macaulay Culkin) leaving him home alone.

As if being left at home by yourself over Christmas isn’t quite bad enough, Kevin also finds his home has become the target for burgling duo Harry (played by Joe Pesci) and Marv (played by Daniel Stern) - known as the Wet Bandits.

20th Century Studios

Of course, little Kevin isn’t going to go down without a fight so he sets about creating a range of traps that are so fiendish they would make Jigsaw proud.

The movie is a Christmas classic and is often given another watch at this time of year - but it seems as though some fans have only just realised that the cop at the start of the film is actually burglar Harry in a costume.

Despite it being a bit of an important plot point - as this is how Harry manages to case the McCallister house before they fly out to France - it seems plenty of folks managed to completely miss it.

Taking to social media, one shocked viewer said: “How old were you when you found out the cop in the beginning of Home Alone is also the robber?

"Because I found out about two minutes ago.”

20th Century Studios

Another said: “Wait y’all omg, why am I just now noticing that the cop in the beginning of Home Alone is the burglar and that’s probably how he knew they was out of town.”

A third commented: “I was today years old when I realised that the burglar (Joe Pesci) in Home Alone was dressed as a police officer in the beginning of the movie.”

And someone else joked: “Every time i re-remember the cop at the beginning of Home Alone is one of the burglars I feel like I should be mentally classified as a fish because it took me like 12 Christmases to put the pieces together.”