At this year’s Detroit Auto Show, there have been a number of unscheduled early reveals. Some have occurred just a day or two in advance of the official unveiling. While others, like the awesome Lexus LF-LC concept, were accidentally exposed weeks in advance of the event. One concept which did manage to stay hidden until its official due date was the Toyota NS4. Toyota had previewed the concept back in late December, publishing a single image and scarce details. But today it’s all out in the open.The Toyota NS4 is an advanced plug-in hybrid concept which the company says; “exemplifies Toyota’s vision for future mobility, with a focus on next generation connectivity and safety.”The NS4′s drivetrain was engineered so that the components were smaller and lighter than anything before, improving both fuel economy and performance. In addition, Toyota’s engineers worked on reducing the all-important charge time.The NS4 concept features Toyota’s latest safety technologies, including a next generation pre-collision system (PCS), adaptive driving beam (ADB) headlights, and blind spot monitor (BSM). PCS features lane departure and pedestrian collision avoidance technologies designed to predict collisions under certain circumstances and help avoid them. The system uses millimeter-wave radar and stereo cameras mounted on the front of the car to detect and react to lane departure, pedestrians, and other vehicles. If it detects a potential collision, the system seeks to avoid other vehicles, road-side obstructions, and pedestrians by applying the brakes and manipulating steering.The Adaptive Driving Beam (ADB) headlights help reduce glare for oncoming drivers and pedestrians. Using a camera mounted behind the front grille and partial shielding inside the headlights, this feature allows drivers to maintain near-high beam illumination to improve nighttime visibility.More passive safety systems on the Toyota NS4 concept include a rain-resistant ‘hydrophobic’ coating on the glass. This treatment improves visibility in wet conditions, allowing the driver to see further and more clearly. In addition, the inner and outer rear view mirrors have been replaced with cameras that provide the driver with a panoramic view to the rear. The rear-view camera relays video to a dashboard-mounted screen, and provides the driver with a much wider field of vision when compared to a traditional rear view mirror.Aside from stuffing the NS4 concept with lots of safety systems, Toyota have also equipped it with an advanced Human-Machine Interface (HMI) which is centred around a multi-touch screen display designed with the look and feel of a smartphone. The HMI provides the user with control of the multimedia systems, air conditioning,  battery-charge and navigation functions. The HMI system is even capable of “learning” driver preferences to anticipate driver responses in specific environments and situations. While developing the HMI, Toyota teamed up with electronics and software giants including Microsoft, Intel and Salesforce.Jim Lentz, president and chief executive officer of Toyota Motor Sales US (Inc.) said of the NS4 concept; “In this digital age, cars are becoming another spoke in the wheel of our electronic connectivity. NS4 demonstrates Toyota’s take on the human connection to the car with technology that considers both emotional and rational relationships, person-to-car and car-to-society.”