What's all this about?

It's a 'new' BMW i3, which has been mildly facelifted, subtly updated inside and given a tiny change to the chassis tech. But that's not the main news, oh no. There's also now a performance variant of BMW's striking electric vehicle (EV), called the i3s.

Shall we start with the vanilla car and work our way up to the hot one?

Ah. We might have oversold precisely how hot the i3s is. So don't get too excited. Anyway, let's do as you say and focus on the regular EV first. A change to the i3's illumination means the front end has changed notably, because - on the old car - the halogen main beam lamps were those round lights down in the bumper. They've gone, replaced by slim units for the front indicators, with the main beams now in the higher clusters and they're fully LED to boot. That's meant the lower front bumper has had to be redrawn, with extra defining lines and a strip of black below the number plate. At the back, a 40mm wider bumper insert with pronounced design creases surrounds the number plate, while the 'eDrive' and 'i3' badges have been pushed further out on the hatch to emphasise the i3's width. Around the sides, nothing has changed, save for extra 19-inch alloy designs and a silver highlight for the roofline.

All good. How about within?

Minimal stuff here. A new interior ambience called Lodge features a 'Solaric Brown' upholstery for the seats that's a mix of climate-active sheep's wool and olive leaf tanned leather. Up on the dash, the 10.25-inch infotainment display is a higher resolution than before, while it also features the six-tile configurable home screen set-up seen in other recently launched and updated BMWs. Additional functionality for the i3 includes Natural Language Understanding, Digital Charging Service, On-Street Parking Information and Apple CarPlay.

And you mentioned a chassis update for the i3?

Yes, BMW has revised the Dynamic Stability Control (DSC) management, specifically calibrating the software to cater for EV running. Rather more brilliantly, the DSC now has a Dynamic Traction Control (DTC) 'halfway-house relaxed' setting incorporated, with BMW saying that - and we're not joking here - you can now enact 'controlled drifts' around corners in your i3. Which is cool.

But there are no power changes here?

Not for the regular i3. Its 170hp/250Nm electric motor still drives the rear wheels and is powered by the larger capacity 94Ah battery pack that was slotted into the BMW in 2016, meaning a theoretical maximum range of 186 miles on a single charge; BMW reckons on more like 125 miles in regular driving conditions. Performance is brisk, with 0-62mph in 7.3 seconds, although the top speed is limited to just 93mph. One side note here: a new, optimised charging cable and i Wallbox home charger with an 11kW output mean the i3 can be juiced up to 112 miles of range in less than three hours. But, other than that, the i3 stays the same. It's the i3s that gets the extra grunt...

What sort of gains are we talking?

Temper your enthusiasm. The i3s is bolstered to the tune of 14hp and 20Nm. Which, as your maths has probably already told you, means 184hp and 270Nm; enough to slash 0.4 seconds off the 0-62mph time, leading to a 6.9-second sprint, and capable of propelling the i3 to the giddy heights of 99mph.

Is that it?!

The i3s gains other upgrades, such as 20-inch, 20mm wider alloy wheels, a 40mm wider rear track, 10mm lower sport suspension, specially adapted Sport Steering, high-gloss black spats over its wheel arches and a high-gloss black insert in the front grille (complete with colour highlight bars), an additional Sport driving mode, revisions to the ASC anti-skid system and special 'i3s' badges/logos for the hatchback and carpet mats inside.

And when can we see this, er, firecracker on the roads?

Both the revised i3 and the new i3s will be on show at the IAA 2017 Frankfurt Motor Show in September, with a market launch in November 2017.