What would you do? #134 - Facing overbet for value

This will probably go down as one of the stranger plays I've ever gotten involved in...

Full Tilt Poker $0.25/$0.50 No Limit Hold'em - 8 players
The Official DeucesCracked.com Hand History Converter

MP2: $50.00
CO: $0.00
BTN: $38.40
SB: $50.00
BB: $16.75
UTG: $73.75 - 50 / 38 / 100% steal / 2.0 aggression factor / 9 hands
Hero (UTG+1): $51.75
MP1: $53.30

Pre Flop: ($0.75) Hero is UTG+1 with Td Kd
UTG calls $0.50, Hero calls $0.50, 4 folds, BB checks
I limp because UTG limped.

Flop: ($1.75) Js 8s 2s (4 players)
BB checks, UTG checks, Hero checks
3 flush already on the board.

Turn: ($1.75) Qc (4 players)
BB checks, UTG checks, Hero bets $1.20, BB folds, UTG calls $1.20
Turned OESD, but I have to discount 2 outs.  Given the interest in this pot (ZERO), I didn't think I would have a problem taking it down right here and now.  WRONG!

River: ($4.15) Ad (3 players)
UTG bets $72.05 all in, Hero requests TIME, Hero ???


Click to see results

Hero calls $50.05 all in
WTF?!?!?!?  At first, I was thinking "autofold."  In fact, I heavily (obviously) weighted my decision towards that choice.  Really; I have $2 invested; should I be putting in another $48 to "look him up?"

• I know very little about my opponent
• He is overbet shoving
• There are not so many limpable hands that beat me, particularly from a UTG limp perspective.

The only hands I could come up with here were AsQx, AsJx, AsKx or even a set, which I doubt would be played so passively given the flopped 3 flush.   Given his propensity for LAGgy play, I gave him some credit for 2 spades, but I just can't see a $4 -> $72 shove with a made flush.  I also can't see him losing 2 streets of value and shoving the river with the flush.  Therefore, I decide on looking him up and am disappointed [obviously] with the results: 

Final Pot: $104.25
UTG shows Tc Kh (a straight, Ace high)
Hero shows Td Kd (a straight, Ace high)
UTG wins $50.65
Hero wins $50.60
(Rake: $3.00)

I think I busted him or someone else did shortly afterward.  He was not a good player :-).