Learn Swedish: Om planen skulle misslyckas, tar kumpanen flyktbilen. - If the plan were to fail, the accomplice takes the getaway car.

Adding skulle to the bare infinitive makes the condition more tentative or hypothetical. While om planen misslyckas simply means 'if the plan fails,' om planen skulle misslyckas emphasizes that failure is a remote possibility, translating perfectly to 'if the plan were to fail' or 'if the plan should fail.'

Why does the main clause use the present tense (tar) instead of a conditional like skulle ta?

Using the present tense tar (takes) after a hypothetical 'if' clause makes the consequence sound like a fixed protocol or a pre-agreed rule. If the speaker had used skulle ta (would take), it would sound more like a general prediction rather than a concrete backup plan.

Is misslyckas a passive verb here because of the -s at the end?

No, it has a completely active meaning ('to fail'). It belongs to a group of words called deponent verbs, which always end in -s but are active in meaning. You have likely encountered this before with common verbs like hoppas (to hope), minnas (to remember), and kännas (to feel).

Why is the word order tar kumpanen instead of kumpanen tar?