Hey, Hey, What Can I Do is the B-side you're looking for.

Yes, the B-side to “Immigrant Song” is “Hey, Hey, What Can I Do.”

It’s a weird little gem—a country-ish folk rock tune that doesn’t sound like anything else Zeppelin did. The vocal arrangement is rare because John Paul Jones actually sings lead alongside Robert Plant, trading lines and harmonizing. That almost never happened on a studio track.

It only appeared on the original 1970 single and didn’t get an album release until Coda decades later. If you only know Zeppelin for heavy riffs, this one will surprise you.

Worth digging up if you want to hear them loosen up and try something different.