Galactic civilisation has collapsed, and is just starting to regroup. You are an ensign on a ship seeking lost worlds. Your ship blows up, but you manage to escape and crash on one of these lost worlds. However, it seems that nobody is home. You have to contact your fleet for a rescue pick-up, and figure out what happened to the resident population. Your companion and aide is Floyd, a somewhat goofy robot you find at the research base where you land.
Although the game starts off in high humour on the ship, things become less goofy on the planet. It's still light-hearted, but the base and the story of its people are realistic enough. The back-story is primarily dumped on you through library facilities you find. The base layout is realistic and complete, generating a strong sense of immersion.
The challenges all fit in naturally with the setting. Most are fairly simple, but there are a few that require inspiration; they're all reasonable, though. There's a good combination of repairing and operating machines, overcoming physical obstacles, and dealing with nasty critters. There are several red herrings, and an optional challenge or two.
It's possible to die, so you'll want to save often. There's always good warning of the danger, at least in hindsight, but you might not realise the warning for what it is until it's too late. You have to manage food and sleep, failure of which can be fatal, so it's a good idea to save, explore and experiment, then restore and do the tasks efficiently. You also have a developing illness, which discourages doddling.
There's at least one dead end, and a few not-quite-dead ends, where you can still complete the game but not to the best ending. You can find yourself on a one way trip to the finale without knowing it and before completing all your optimal-ending tasks. However, the causes will be clear in hindsight. More reasons to save often.
The parser is generally good, but I noticed a few hiccoughs. pour-ing the flask didn't work, nor did swipe-ing the access cards.
Planetfall has an excellent sense of place. With a nicely varied set of challenges, it's a fun place to visit.