Help !! 2 yr old DS STILL up 2 hours after being put to bed

[TuTu]

DS who is 2 moved into bed about a month ago, and all went brilliantly to begin with. The odd night lately he has got out of bed after being put down, but he would only ever get out once and when I shouted "BED" he would put his head down and trundle back there and that would be the end of it.
Tonight it has been unreal. He has been up and down more times than I could count, and been in every room upstairs (including his older brother's). I've tried lifting him and just saying "Bed", I've tried holding his door closed but still listening to him playing with his toys in his room. He just seems to think me lifting him back in is a new fab game, even though I am really stern with him.
HELP!!!

does he have a daytime nap? ds1 started staying up playing til 9pm recently and he just wasn't tired as he was having a 2hr nap during the day, cutting out the nap means he goes to bed at 7 and is asleep within minutes!

Yes he loves his nap and I lift him after 1.5 hrs. I think you're right about having to drop this - its hard though as its only time i get to spend with older ds or get a cuppa!

i know it is soo hard when they give up the naps but sleep at night is more important iyswim!! i tried shortening the naps at first but even an hour in the day meant he wouldn't settle at bedtime
god it's a looong day when they don't nap. esp when you have 2!
good luck