Harvey Keitel and his boys don't get the back garden finished in time. Greg has another fight with Pam, and decides to spend the night in their unfinished new home. Andi Garcia drops by with some wine and Chinese Food.
I know what you're thinking - she's working undercover, sent by Jack to seduce Greg -- a similar plan as to what happened with Doctor Bob, who failed that test. But no, nothing that "clever" in this one. She's just a good looking, horny drug rep with a thing for Greg.
She takes some pills and makes her move - as Jack shows up and gets the wrong impression. Jack leaves, now determined to bring Pam and Kevin back together again. Andi throws Greg's phone into the garden pit, throws in Greg, and then dives bombs him - kncoking them both out.
Next morning Bernie shows up and takes Greg to the party - held at Kevin's ranch. Kevin is turning on some moves on a rope in his Moroccan themed event. Greg shows up, apologises to Pam, who again for the third time agrees that her dad is mental, and all is forgiven.
This all brings a tear to Kevin's eyes, who slips and falls from the ropes.
Jack doesn't buy it. Jack and Greg finally get it out, taking the fight to a bouncy castle and later to the ball pool. You'll have seen all this in the trailers that were everywhere.
Jack soon has another heart attack. Kevin is useless, so Greg steps up and saves his life. When the paramedics arrive Jack forgives Greg, and tells him that he was always the first choice (doesn't make sense) and he is "The Greg Focker". Greg, for some reason, is honoured.
In an extra DVD scene, 4 months later Kevin calls round Greg's home to say his goodbyes as he is about to jet off with Andi.
Six months later from the heart attack, the 3 families are back together again for Christmas (I think). We hear the news that the Fockers have bought a house a few doors down, and now Jack wants to move into the same street too. Greg is horrified.
During the credits, Jack uses this new thing called "Google" and finds the presentation Greg gave at the drug conference on YouTube, mainly focusing on stories about Jack it seems and a little light on content about the actual drug itself.