It's not as sinister as it sounds, of course. The Prime members-only service, called Amazon Key, uses a smart lock and connected camera. When a delivery is made the courier scans the package's barcode which sends an access request to Amazon's cloud. When it grants permission, the camera starts recording, the courier swipes a prompt on their app and then your door unlocks. They leave the package by the door and relock it on their way out. You'll get a notification that the delivery has been made, along with a video of the drop-off to reassure you everything was done above board.

Amazon has designed the service with deliveries in mind, but Key has a bunch of other uses, too. For example, you can use it to give permanent access to people you trust or temporary access to visitors such as dog-walkers, cleaners or guests (this could be especially helpful for Airbnb hosts).

The service can only be used with a connected camera (which makes sense given the potential privacy issues at hand), but not just any camera: it has to be Amazon's Cloud Cam. The good news is that it's a decent bit of kit in its own right, acting as a home security device and responding to voice commands, provided you have an Alexa-enabled device including the Echo Show, Echo Spot, Fire TV and Fire tablets that support Alexa. It also boasts night vision and two-way audio.

A smart lock, Cloud Cam and installation will set you back $250 (Prime customers can preorder the camera today, the Key service becomes available on November 8). There are no extra charges, but a forthcoming subscription service will give you access to additional features such as footage archiving, motion detection and zone monitoring.

The service -- while set to revolutionize the delivery market -- feels like a huge test of trust. Are people prepared to let strangers into their homes while they're not there, just because it makes getting packages a bit easier? How do security concerns stack up against ultra-convenience? Some might argue the service launches us ever further into a sci-fi-like existence where computers monitor and guide our every move. But as Amazon has already demonstrated with its futuristic drone delivery aspirations and super-connected, Alexa-managed homes, we're not too far away from that reality already.