In "Grand Theft Auto IV," there are two possible outcomes for Roman. In the first, he is killed at his own wedding. In the second, he lives and is happily married. If you want to save Roman from dying, you need to make the correct series of choices in the mission "One Last Thing." However, if you choose to save Roman, it is important to be aware that Kate will die instead.
At the start of this mission, you will meet Jimmy at Honkers in Tudor. He will ask for your help and tell you that he has found a buyer for the heroin you acquired earlier in the game. In order to sell it, you will need to work with Dmitri. However, because of Dmitri's past betrayal, you are hesitant to do so.
Roman and Kate's Advice
You call Roman and Kate for advice on what to do. Roman says you should go through with the deal and forget about the past. Kate says that you shouldn't compromise, regardless of how much money is involved.
Make Your Choice
After speaking to Roman and Kate, you will be given two options: deal or revenge. If you click on the deal option, you will give Dmitri the heroin and take the money from the buyers. If you click on the revenge option, you will kill Dmitri.
If you take the deal and work with Dmitri, he will send hit men to Roman's wedding to try to kill you. In the scuffle, Roman will be accidentally shot. If you choose revenge and kill Dmitri, Pegorino will come to the wedding to try to kill you, but will accidentally shoot Kate instead.