I want to load a different version of the files that exist in another branch into my current branch.

`git help checkout` says:

```
DESCRIPTION
   Updates files in the working tree to match the version in the index or
   the specified tree. If no paths are given, git checkout will also
   update HEAD to set the specified branch as the current branch.

```

Is there a way to checkout all those files, but *not* update HEAD?