I insta called this hand in a tournament without much thought but afterwards I started to think if it's ever a fold.

PokerStars - 25/50 NL - Holdem - 9 players
Hand converted by PokerTracker 4

UTG: 132.34 BB
Hero (UTG+1): 53.2 BB
MP: 60 BB
MP+1: 60 BB
MP+2: 87.96 BB
CO: 89.44 BB
BTN: 127.38 BB
SB: 64.38 BB
BB: 111.58 BB

SB posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 1.5 BB) Hero has K K

fold, Hero raises to 3 BB, fold, MP+1 raises to 60 BB and is all-in, fold, fold, fold, SB raises to 64.38 BB and is all-in, BB raises to 111.58 BB and is all-in, Hero calls 50.2 BB and is all-in

Flop: (241.96 BB, 4 players) J 4 Q

Turn: (241.96 BB, 4 players) 3

River: (241.96 BB, 4 players) 7

SB shows 9 A (High Card, Ace)

Main Pot [212.8 BB]: (Pre 6%, Flop 3%, Turn 0%)
Side Pot#1 [20.4 BB]: (Pre 7%, Flop 3%, Turn 0%)
Side Pot#2 [8.76 BB]: (Pre 7%, Flop 3%, Turn 0%)

BB shows A A (One Pair, Aces)

Main Pot [212.8 BB]: (Pre 63%, Flop 78%, Turn 90%)
Side Pot#1 [20.4 BB]: (Pre 79%, Flop 88%, Turn 95%)
Side Pot#2 [8.76 BB]: (Pre 93%, Flop 97%, Turn 100%)

MP+1 shows A Q (One Pair, Queens)

Main Pot [212.8 BB]: (Pre 12%, Flop 9%, Turn 5%)
Side Pot#1 [20.4 BB]: (Pre 14%, Flop 10%, Turn 5%)

Hero shows K K (One Pair, Kings)

Main Pot [212.8 BB]: (Pre 18%, Flop 10%, Turn 5%)

BB wins 241.96 BB

Trickier spot than someone might expect, reads on other players make the difference here

No its never a fold if they got it they got it.

Not a tricky spot - just don't fold Kings pre at this kind of depth

Notice that even in this scenario we have 18% equity on the flop where we need about 23% to make it a break- even call - so we lose less than 12bb in chip EV - and of course there are many scenarios where we are massively +cEV

Thanks for the answers. Would you do the same if you had a 150BB stack? I assumed I was going up against Ax but not AA when there were already 2 aces out of the pool..