These are not exactly my own favourite comics (there is no Marshal Law, Skreemer, Claremont-Byrne run of X-Men, Seaguy, Flaming Carrot or any of the comics I grew up reading in 2000 AD). Rather these are books that I think have the kind of crossover appeal that would make them interesting to someone who has not been reading comics for decades.
Batman: the Dark Knight Returns, by Frank Miller, Klaus Jansen & Lynn Varley
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Frank Miller has written and drawn a lot of comics and many of them are dreadful, though some of his Daredevil and Sin City comics might be worth your while.
From Hell, by Alan Moore and Eddie Campbell
This is Alan Moore's other masterpiece. but very different to Watchmen. Instead of the 1980s superhero costumes and clean lines of Dave Gibbons' art, here we find ourselves back in 1888, with Victorian London rendered in gloriously scratchy art by Eddie Campbell. The book is not for the faint-hearted, as it deals with the Whitechapel murders of that year and is largely told from the point of view of the murderer. For me a big part of its appeal lies in its exposition of Moore's strange occult ideas.
I myself have attempted to re-enact chapter 4 of From Hell (which does not feature any murders, I hasten to add).
Memoir comics became a bit thing. This is Satrapi's memoir of her time growing up in Iran during the Islamic Revolution and then during her time outside the country, all drawn in a faux naive childlike style of blocky art with thick lines and large areas of black ink. One thing that is intriguing about this book is how unsparing Satrapi is about the more unsavoury aspects of her own past actions.
Maus, by Art Spiegelman
Neil Gaiman made his name writing Sandman, the goth-friendly comic about Morpheus, Lord of the Dreamworld. It was big in the early 1990s and while I have not read it in years I remember it fondly for its cleverness, wry humour, and embrace of every strange mythological thing Gaiman could lay his hands on. Preludes and Nocturnes is the first book in the series; if you like it there are plenty more to follow.
Originally appearing in the pages of the magazine Love & Rockets, this comic tells the story of two Latina women in some American town, as they fall in love, play in punk bands and hang out with friends. The Girl from H.O.P.P.E.R.S. is the second book in the series but it is probably the best one to start with as the first is famously a bit hard to get into. FULL DISCLOSURE: I am not mad on comics by Jaime Hernandez myself but loads of people love them, so you might too.
This also appeared originally in the magazine Love & Rockets. Where his brother's stories are set among the Latino community in the United States, Gilbert Hernandez deals with people who are still living in Central America, in this case the fictional backwater town of Palomar (though later volumes follow characters who have emigrated to Los Angeles). For me there is an incredible richness to the Palomar narrative and a depth of characterisation seldom seen in comics, like his brother's work very focussed on women characters, though not exclusively so. Heartbreak Soup is the first of the Palomar collections; if you like it then you will love Human Disastrophism, the second volume.
A comic by Joe Sacco
Joe Sacco has written and drawn a number of books of what are basically comics journalism, mostly focused on the Palestinian issue or the war of the early 1990s in the former Yugoslavia. All of his books are worth reading but I particularly recommend The Fixer, which deals with Neven, a fixer character he encountered in Sarajevo when he was researching his book Safe Area Gorazde. Neven is a larger than life character with a questionable relationship to the truth, someone who has both done astonishing things in the course of the war and a bullshitter who shamelessly exaggerates his exploits to impress the gullible.
FULL EMBARRASSING DISCLOSURE: I have never actually read a Joe Sacco book all the way through from cover to cover but I have greatly enjoyed skimming the various copies in Panda Mansions.
Hate: Hey Buddy!, by Peter Bagge
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Dan Clowes started off creating strips that appeared in Eightball and went on to write and draw comics that appeared in standalone books. He has a singular aesthetic often focussed on people who seem to be drained of emotion and hovering on the brink of a breakdown; if I am feeling depressed I often think of myself as having become an Eightball character. Ghostworld (adapted into a popular film) is probably his best known work though I have always found that one a bit dull. More interesting to me titles include Like A Velvet Glove Cast In Iron, The Death Ray, Ice Haven, Wilson, and David Boring.
The author looks back on her childhood and adolescence, during which time she comes out as a lesbian. Her father also kills himself and is revealed as a closeted homosexual involved in legally dubious relationships with underage boys. I have not actually read this book myself but it comes highly recommended and is always near the top of comic books I plan on reading in the near future.
Sweet Tooth: Out of the Deep Woods, by Jeff Lemire
So that is my list of comics I am recommending to people who have read Watchmen and what to further explore the comics world. I am aware that the list of creators is a bit white Anglophone male, which reflects the comics I have been exposed to over the years. They are also mostly from quite a while ago, for similar reasons. I invite readers to recommend their own favourites in the comments.
image sources:
Batman and punk (DC Comics Database)
From Hell pentagram (Den of Geek: 13 Essential Horror Comics)
Marjane Satrapi and Michael Jackson (The Comics Reporter: Bart Beaty On Persepolis)
Maus (Comics Alliance: Examining Art Spiegelman's 'Maus')
Sandman (Bookworm the Hippie: Branching out to Graphic Novels)
The Girl from H.O.P.P.E.R.S. (Fantagraphics: The Girl from H.O.P.P.E.R.S.)
Heartbreak Soup (Fantagraphics: Heartbreak Soup)
The Screening, from Footnotes in Gaza (Art Threat: interview with Joe Sacco)
Buddy Bradley from Hate (Guasíbilis: Buddy Bradley en "Odio los sábados por la noche")
The man who could not digest ketchup, from Like A Velvet Glove Cast In Iron (The Slings and Arrows Graphic Novel Guide: Like A Velvet Glove Cast In Iron)
Panel from Fun Home (Fifty Books Project 2016: Fun Home)
Gus & Jeppard from Sweet Tooth (The Comics Journal - From Essex County to DC: The Transplanting of Jeff Lemire)