John Oliver in "Last Week Tonight With John Oliver"

John Oliver sure won't be lacking for subject matter when his weekly talk show returns. The British comedian, who rose to fame as a writer and correspondent for Jon Stewart's "The Daily Show," is never one to shy away from talking about tough topics, and after a three-month hiatus, "Last Week Tonight With John Oliver" returns for a fourth season Sunday, Feb. 12, on HBO.

In the season finale in November, he bid 2016 an unceremonious farewell, blowing up a ginormous "2016" sign and walking off without looking at the explosion. A lot has transpired in the short months since, and since season 3 of "Last Week Tonight" touched heavily on Donald Trump's presidential campaign, there's little doubt that it will come up again.

But don't think that just because President Trump dominates headlines -- "You can't take much pride from a series of comedy layups," Oliver told Vulture last year in his quintessential self-deprecating way -- that he won't tackle other stories. The show has touched on a variety of topics since its premiere in 2014, from a controversy surrounding Fanta and the leap second to paid parental leave and payday loans. Despite the seriousness of the topics, he insists that "Last Week Tonight" is a comedy show, not a news magazine.

"News is absolutely not our lane," he said in the Vulture interview. "Saying someone watches the show for news is like saying to a musician, 'A lot of people use your music to work out. Do you make workout music?' No, this isn't designed for the gym. We're obsessed about making sure that all the things that we say are accurate, but that's only because those things are the structural foundation upon which the jokes are based. You remove that, and your jokes are all nonsense. It's a comedy show."

Comedy show or not, Oliver and his staff have created a series that fans and critics alike are lapping up. It has garnered praise from the likes of Time magazine, Entertainment Weekly, Associated Press and the New York Times, among others, and has received ringing endorsements from the various awards organizations. "Last Week Tonight" has won a Critics' Choice Television Award; a Peabody Award, which recognizes "distinguished and meritorious public service" by U.S. TV stations and networks; a Writers Guild of America award; and four Emmys, including Outstanding Writing for a Variety Series and Outstanding Variety Talk Series last year.

The praise and accolades are well deserved, especially since the series has proven to be pretty influential.

In season 2, Oliver hired a team of lawyers to establish the Our Lady of Perpetual Exemption church as part of a segment designed to show viewers just how easy it was to set up a tax-exempt religious institution. Donations from around the world poured in, but the church was dissolved in September, and the money given to Doctors Without Borders. Another season 2 episode saw Oliver sit down for a very secret interview with NSA whistleblower Edward Snowden, which made headlines around the world, and last season he did a segment on debt buying, during which he bought -- and forgave -- millions of dollars worth of bad medical debt.

Keegan-Michael Key and John Oliver as seen in "Last Week Tonight With John Oliver"

Long before he was discussing opioid abuse or tearing into multilevel marketing, Oliver was a correspondent with "The Daily Show," then under the tutelage of Jon Stewart ("Rosewater," 2015). Oliver first appeared in the late-night satire talk show in the summer of 2006 -- not a day after arriving in the U.S. from Britain -- and was an instant hit. Over the next seven years, he was part of some iconic bits, and even occupied the host's chair when Stewart went away for 12 weeks to film his directorial debut.

"The fact that he asked me to take over the show when he was away felt like such a huge leap of faith from him," Oliver told Vulture, "and I thought that faith may have been a little bit misplaced."

Clearly Stewart was on to something, and he gave Oliver a much-needed little shove upon his return. "He said to me, 'We need to talk about what you're going to do next,'" Oliver said. "In your head, that sounds like you're being fired, so that was pretty frightening. But what he wanted to say was that I needed to think about what I wanted to do next. He knew it was going to be hard to go back to my old job after having filled in for him. He was a little bit of a mother bird pushing me out of the nest. When I mentioned the offer from HBO, his face changed, and he said, 'You would be insane not to take that.'"

Luckily, and despite what he may say, Oliver isn't insane, and viewers have benefited immensely from his dry wit and the self-deprecating humor. He shines a light on stories many people wouldn't give a second thought to, and though he may deny being a news program or a journalist, he's definitely shown a propensity for digging deep into issues.

Season 4 of "Last Week Tonight With John Oliver" premieres Sunday, Feb. 12, on HBO.