Although not required to play the game, it’s strongly recommended you finish Half-Life 2 before you venture into Episode 1, as your first objective in Half-Life 2 Episode 1 is to return to the final scene of the original to help save the imprisoned remnants of the human race.

Instead of dying at the hands of a massive explosion, protagonist Gordon Freeman and sidekick Alyx are saved at the last minute by alien sympathisers. After a brief conversation with Alyx’s father, you discover that City 17, the game’s main locale, is in disarray and citizens are attempting to escape its confines. It’s up to you to buy them some time by cleaning up the mess.

For the next four and a half hours it’s classic Half-Life 2 gameplay, right down to the (now unoriginal) physics puzzles and the now stale heavily scripted sequences. In fact, Episode 1 plays so much like Half-Life 2 it borders on uninspired.

Add to this that a third of your playtime is spent watching Alyx do almost everything and the first half spent armed with nothing but the Gravity Gun, and Episode 1 is just plain frustrating. It’s hard to think of anything more depressing than hiding behind a seemingly invincible Alyx (with pockets of never-ending bullets), throwing rocks at enemies with the Gravity Gun because it’s the only way you can defend yourself. When you do eventually get the crowbar, you’ll equip it perhaps twice before you realise you managed three hours of the game without it.

Half-Life 2 Episode 1 looks great thanks to an updated Source engine and the game plays with the entertaining story-driven linearity of a Half-Life game. But by today’s standards it’s uninteresting and at times, an effort to play. Valve desperately needs to take an honest look at the core gameplay that it has relied on for so long before Episode 2 arrives.