The dad-stepdad double team of Brad Whitaker (Will Ferrell) and Dusty Mayron (Mark Wahlberg) seem to have put their previous warring ways behind them, but all bets are off when their respective fathers - sweet-natured hug enthusiast Don (John Lithgow) and womanising ex-astronaut Kurt (Mel Gibson) - fly in for the holidays. Before long old tensions are bubbling back to the surface and all-out chaos breaks out - one particular episode involving a runaway snow blower and a doomed Christmas display. Linda Cardellini is back as Brad's wife Sara, and look out for a late cameo from hero pilot Chesley 'Sully' Sullenberger.