Shah Rukh Khan is working day and night to make his most ambitious project "Ra.One" a huge success but the actor is not letting his energy levels go down.

"Distinction between night and day waning. having dinner at 6 a.m. energy levels still high. joules to joules i can take on anyone & still smile, " Shah Rukh wrote on microblogging site Twitter.

"For those who think my energy is comparable to anyone else's... I have only one thing to say... u have a lot to learn baby!! Ha ha, " he further posted.

King Khan's superhero film "Ra.One" is slated for a Diwali release and also stars Kareena Kapoor and Arjun Rampal.