50NL facing overbet on the river

[Miyogi]

So do I make the heroic call on the river vs. the overbet or do I fold. Note, vs. a villian with lower aggression I prolly fold. Villian is 33/11/4.75

Full Tilt Poker - No Limit Hold'em Cash Game - $0.25/$0.50 Blinds - 5 Players - (LegoPoker HH Converter (http://www.legopoker.com/hh))

SB: $115.65
<font color="black">BB: $36.00</font>
UTG: $32.50
<font color="black">Hero (CO): $58.45</font>
<font color="black">BTN: $86.45</font>

<font color="black">Preflop:</font> Hero is dealt Ahttp://legopoker.com/hh/images/diamond.gif Khttp://legopoker.com/hh/images/club.gif (5 Players)
UTG folds, <font color="red">Hero raises to $1.75</font>, BTN calls $1.75, SB folds, BB calls $1.25

<font color="black">Flop:</font> ($5.50) K/images/graemlins/heart.gif 2/images/graemlins/heart.gif 4/images/graemlins/heart.gif (3 Players)
BB checks, <font color="red">Hero bets $5.00</font>, BTN calls $5.00, BB folds

<font color="black">Turn:</font> ($15.50) 4http://legopoker.com/hh/images/club.gif (2 Players)
<font color="red">Hero bets $9.00</font>, BTN calls $9.00

<font color="black">River:</font> ($33.50) 3http://legopoker.com/hh/images/club.gif (2 Players)
Hero checks, <font color="red">BTN bets all-in for $70.70</font>

Pot Size: $104.20

[RingoStar]

I would fold. Probably would have checked the turn though.