Bodyguard (2018)

The 2018 BBC thriller, and one of the lightest commitments here for the biggest gasps. It opens with a long, nerve-shredding sequence on a commuter train that tells your companion exactly what kind of ride this is, then keeps finding new ways to pull the floor away. Richard Madden plays a troubled war veteran assigned to protect a controversial politician, and the uneasy pull between them is what makes the rewatch rewarding. Its finale drew 17.1 million UK viewers, a record for any drama episode since current records began in 2002, which tells you how few people managed to stop.