Pennyworth is a show that you might be forgiven for forgetting it existed because it very much felt like a Batman show in name only. It's not even really a Batman show, because as its title suggests, it focused on the origins of The Dark Knight's faithful butler Alfred Pennyworth.
Jack Bannon played the young comic book character long before his vigilante butler days, as the show dramatized how Alfred first met Thomas Wayne and struck up a lifelong friendship with him. It also revealed how he acquired the skills that would come in handy to Batman in the future, showcasing how he was a former SAS agent and how he would have to put those skills to use whenever he found himself in hot water.
The show is often overlooked because it's barely a comic book show, but that shouldn't discount the fact that it's a great crime thriller in and of itself, functioning very much like a British drama that you might see on ITV in the evenings after Coronation Street. Bannon was wonderful as Alfred and the show went a long way in highlighting how there is so much more to Mr. Pennyworth than the butler he is known for being.
As a Batman show it falls a little short (which explains its placement on this list), but as a TV series, it's one of the strongest original adaptations of a Batman character we've seen.