The gun is already in the hands of Gibbons/Frost, who uses it to knock out Demetri, and spirit him away. That's still a ways away from Mark killing Demetri with that gun - what Nhadra (played by Behrooz's mother from 24) - saw in her flashforward. We should find out how that plays out next week.
Meanwhile, Lloyd and Olivia are moving closer together, despite Olivia's protestations. After splitting with Mark - because she wanted them to go someplace safe together, and he wanted to stay and face the paradoxical music in LA - Olivia ends up kissing Lloyd, in a lot more than a peck. I have to say - infuriating person that I am - that although I've found Mark unsympathetic for most of the series, I felt bad to see Olivia and Lloyd getting together, and am now more or less rooting for Mark.
And Olivia - and Mark - may soon have bigger problems. Gibbons/Frost now also has Charlie Benford, in addition to Demetri, in his possession. If Mark comes after her, and there's some kind of gunfire, that could be the way Nhadra's flashforward about Demetri and Mark's gun comes to be, after all...
5-min podcast review of FlashForward
See also FlashForward Debuts and Oceanic Airlines as a Portal Between FlashForward and Lost ... 1.2: Proofs and Defiance of Inevitability ... 1.3: Conficting Visions and Futures ... 1.4: FlashForward Meets Shaft and House ... Drunk FlashForwarding in 1.5 ... Across the Universe in FlashForward 1.6 ... FlashForward 1.7: The Future Can Be ... FlashForward 1.8: The Nightie as a Grain of Sand ... FlashForward 1.9: Shelter from the Storm ... Olivia Benford at Harvard in Flashforward 1.10 ... Flashforward 1.12 Parts 1 and 2 ... FlashForward 1.13: Aaron's Daughter, Mark's Gun, and Magpies ... FlashForward 1.14: Somalia, LA, Fate Irresistible and Resistible ... FlashForward 1.15: Who's That Lady?
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