One storyline is going to run through the sixth season of ABB FIA Formula E in 2019/20, the respective fates of the two new teams on the grid: Porsche and Mercedes.
Each is arriving in the electric championship after rising to the top and then dominating series elsewhere. In Mercedes' case, it is still ruling Formula 1. FE is a series that seeks to head off domination through regulation - as many do - but, judging by the success spread of its most recent seasons, it is working. Success is not guaranteed in this championship, no matter how big a budget or motorsport legacy a team possesses - just ask Jaguar.
That's what is going to make this storyline so captivating. Will FE's established squads see off the challenge from the newcomers? Or will Porsche and Mercedes do what Porsche and Mercedes do and ultimately prevail?