The lost boys arrived home on Wednesday.

Pete Alonso and Francisco Lindor had disappeared in the Mets lineup, to the point it was conceivable they were ushered into the witness protection program.

It turns out they were hiding in plain sight.

Alonso and Lindor combined on this day for five RBIs in leading a 6-3 victory over the Angels at Citi Field to complete a three-game sweep.

It was the fourth straight win for the Mets, matching their longest streak in six weeks, and it moved them back into first place by a half-game over the Phillies.

Lindor, hitless for a career-high 31 at-bats, stroked an RBI single in the third and repeated the act in the fourth. In between, Alonso’s thunder gave the Mets an early cushion for the first time since the All-Star break.

Alonso, who began the day in a 2-for-33 rut and hitless in 13 at-bats, crushed a three-run homer in the third.

The 439-foot rocket to left field was No. 248 for Alonso, leaving him within four homers of Darryl Strawberry’s franchise record.

Alonso hadn’t homered (excluding the All-Star game) since July 8 in Baltimore.

“It’s fun whenever the lineup is clicking,” said Lindor, who finished 2-for-4 with two RBIs. “[Brandon] Nimmo is doing fantastic, the bottom of the order has been doing fantastic, and then today Pete with a big at-bat … it’s definitely fun to have guys seeing success.”

Lindor was philosophical about his own situation.

“When you are good, you are good,” he said. “When you suck, you suck.”

As much as Alonso enjoyed his homer, he said his seventh-inning single to right field on an inside-out swing might have been a better sign.

“If I am staying inside the ball and staying to the big part of the field, if that’s my miss, then I am in a really good spot,” Alonso said. “The homer is obviously super great, but when I am hitting the ball to the big part of the field, that’s when I feel good.”

Sean Manaea, in his third appearance off the injured list, pitched five innings and allowed one earned run on two hits with five strikeouts and two walks.

The left-hander extended to 82 pitches after throwing 69 in his previous appearance.

Manaea started with a flourish, striking out the side to begin the game, but a taxing second inning in which he loaded the bases (including two walks) cost him an opportunity to work deeper than the fifth.

But Manaea retired the final seven batters he faced after surrendering a third-inning homer to Mike Trout.

“I feel like he was grinding out there,” manager Carlos Mendoza said. “But he found a way to get through five innings.”

Nimmo homered leading off the first, continuing his superb play.

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Over his past 50 games, Nimmo — who owns a 17-game on-base streak — has produced a .918 OPS and his 59 hits during that stretch lead the National League.

Trout’s two-out solo homer in the third tied it 1-1. It came on a 2-2 fastball gave him 999 RBIs for his career.

But the Mets took control in the bottom of the inning. After Tyrone Taylor walked leading off and Nimmo was plunked, Lindor delivered with his drought-busting RBI single to give the Mets a 2-1 lead.

Alonso, with one out, unloaded with a blast to the second deck in left field.

“We’re going to need those guys,” Mendoza said, referring to Lindor and Alonso. “We know they are going through it, but they are too good of hitters, too good of players.”

Lindor built momentum with an RBI single in the fourth that buried the Angels in a 6-1 hole. Mark Vientos’ leadoff double fueled the rally.

José Buttó, in his first appearance off the IL, allowed two runs in the seventh before Brooks Raley retired Trout, the potential tying run, to end the threat.

Buttó surrendered three hits in the inning, including an RBI double to Chris Taylor.

Raley recorded two outs in the eighth before Edwin Díaz was summoned to face Travis d’Arnaud with a runner at first base.

Díaz drilled d’Arnaud with a full-count slider but struck out Luis Rengifo to end the inning.

All three called strikes by plate umpire Erich Bacchus appeared off the plate, leading to Angels interim manager Ray Montgomery’s ejection in the bottom of the inning.

Díaz began the ninth by drilling Taylor in the left ear flap with a 96 mph fastball but rebounded to get three outs for his 21st save in 23 chances.