In the second season of Star Trek: Picard, the good admiral (Patrick Stewart) is approached by his old rival, the impostor space god Q (John de Lannis) for a new challenge. Q digs out the fingers and throws Picard into an alternate universe where Earth has become a galaxy-wide tyrannical force dedicated to the extermination of its perceived enemies. Earth has already driven the Romulans and Klingons to extinction, and now it prepares to execute the last known Borg (Annie Verching). That's pretty grim. Picard, occupying the space of his tyrannical interdimensional counterpart, must gather his friends (Q conveniently teleports several of them into the evil universe as well), then travel back in time to 2024 to discover how he came to be the evil universe.

At the end of the season, it's revealed that Q only played his little time travel with Picard as a sort of sad farewell. Q was previously thought to be immortal, but he was actually nearing the end of his life, and his powers were waning. He used some of his last bits of magic to test Picard, hoping to bond with him. The season ends with Picard and Q hugging each other warmly goodbye.

This was a relatively restrained conclusion for the character, considering how stupid he had been in the past. There was an episode of Star Trek: The Next Generation in which Q transformed Picard and his crew into Robin Hood charactersfor example. In another episode, to celebrate a personal milestone, Q appeared on the bridge of the Enterprise with a magically manifested mariachi band. Q, in case you couldn't tell, usually brings a lot of swagger to Star Trek.

When it came to Picard, however, De Lannis preferred to be a little less funny. He even made a special request in that direction.

Note that Star Trek: Picard served mainly as a comeback series, catching up with Jean-Luc Picard some 20 years since his last appearance (in the 2002 feature film Star Trek: Nemesis). Many episodes of Picard brought back familiar faces from Picard's world, including Q, Guinan (Whoopi Goldberg) and most of the Star Trek: The Next Generation cast. Stewart agreed to return for the entire Picard series, but De Lancey needed convincing.

De Lancey was worried that he, now in his mid-70s, would be asked to be the same Picard as he had been decades earlier in the Robin Hood episode. Fortunately, the producers of "Picard" took it easy on him. As de Lannis explained to him Newsweek in 2022:

"I sat down and said, 'Look, the first thing I want to know is: You're not going to put me in those tights again, are you?' Because if so, the deal is off! They said "No, no, no, no, we're going for a different feel." I looked a lot like I do now. And I said, 'So it's not time for the Mariachi band?' And they said, 'No.'"

Q "died" at the end of Picard's second season, happy to have given his old friend one last challenge. His appearance was both menacing and sentimental; there were no mariachi bands, and Q himself wore a tasteful black coat. Of course, since Q doesn't experience time linearly, he also returned at the end of Picard's third season to confront Picard's grown son, Jack (Ed Spellers). Although it seems highly unlikely, time will tell if Q appears the proposed Star Trek: Legacy.