Each program consists of a variety of entertaining dialogues introduced briefly in English, and then spoken entirely in the target foreign language. The vignette is first heard at a normal conversational rate, then at a slower rate to aid comprehension. The same dialogue is then repeated at the normal conversational rate used by native speakers.
"Immersionplus German" is a collection of moderately entertaining dialogues in German, voiced by native speakers. Each dialogue is repeated three times -- first time with the natural speed, then slowed down, then again with the natural speed. This approach makes this audiobook a perfect tool for improving listening comprehension. I think the level is at least high intermediate (B2).
There are also Immersionplus dialogues in French, Italian and Spanish. As far as I remember, the content is the same, at least for some of the dialogues (I listened to those many years ago).