Match ends, Watford 5, Charlton Athletic 0.
New Charlton boss Guy Luzon was left under no illusions about his task as they were thrashed at Watford.
Craig Cathcart fired the hosts ahead before Troy Deeney doubled their advantage with a cool finish after Gabriele Angella's high through ball.
Odion Ighalo slotted in from close range just before half-time and later headed in Daniel Tozser's corner.
Tozser himself added a late fifth with a curling, 25-yard free-kick to complete a torrid day for the visitors.
Charlton remain without a win since 8 November and have now lost four of their last five league games.
New head coach Luzon, appointed on Wednesday, was unable to take charge for the first time because of a work permit issue.
The game was in total contrast to the Addicks' 1-0 win over Watford at The Valley in September.
Goalkeeper Neil Etheridge did well to prevent the hosts scoring even more, producing a series of fine saves to deny Deeney, who could have had a hat-trick to mark his 200th appearance for the club.
However, he did succeed in netting his 10th of the season, slotting home while under pressure from Andre Bikey, for what was arguably the game's crucial goal.
Charlton appeared to lack belief after that and their best chance of a goal came and went when Bikey headed Callum Harriott's cross wide.
The Addicks were left 16th in the Championship table, eight points above the relegation zone.
Watford's win kept them in the play-off places, one point above seventh-placed Norwich.
Watford manager Slavisa Jokanovic: "I must be happy with our performance. I am very happy my team is pressing two minutes before the end of the game. This is why they played a good game.
"I speak about the team. It's not [about goalscorers] Troy Deeney and Odion Ighalo - they played very well but all the team played very well. It's not a question about one player or two players.
"The result isn't always important if you're working altogether, if you are compact and if you have a small distance between the lines. If we can compete we can lose or draw or win the games, but if I must lose a game I prefer it this way."
Charlton first-team coach Damian Matthew: "It's been a tough week for the players, a tough week for the club. But all we can do is dust ourselves down, get back on the training pitch and look to improve.
"We're disappointed in the overall result but the first goal is crucial in the Championship, especially in the situation we're in at the moment.
"That was one of our targets - to be dominant in the first 15 minutes. I thought we started the game brightly, we pressed well, but you've got to take those chances and the players were disappointed with that.
"They're top drawer, a good side and we wish them all the best, but from a personal point of view we were disappointed with the overall result."
- 3MunariSubstituted forPudilat 21'minutes
- 21AnyaSubstituted forByersat 82'minutes
- 24IghaloSubstituted forVydraat 75'minutes
- 20SollyBooked at 5mins
- 26Ben Haim
- 6Bikey AmougouBooked at 90mins
- 2WilsonSubstituted forWattat 45'minutes
- 7Berg GudmundssonSubstituted forGomezat 75'minutes
- 14VetokeleSubstituted forChurchat 65'minutes
- Darren Bond
- Shots on Target
Second Half ends, Watford 5, Charlton Athletic 0.
Goal! Watford 5, Charlton Athletic 0. Daniel Tözsér (Watford) from a free kick with a left footed shot to the bottom right corner.
André Bikey (Charlton Athletic) is shown the yellow card for a bad foul.
Matej Vydra (Watford) wins a free kick in the attacking half.
Foul by André Bikey (Charlton Athletic).
Foul by George Byers (Watford).
Chris Solly (Charlton Athletic) wins a free kick in the attacking half.
Attempt missed. Daniel Pudil (Watford) left footed shot from outside the box misses to the right.
George Byers (Watford) wins a free kick in the defensive half.
Foul by Yoni Buyens (Charlton Athletic).
Juan Carlos Paredes (Watford) wins a free kick in the defensive half.
Foul by Callum Harriott (Charlton Athletic).
Foul by George Byers (Watford).
Tony Watt (Charlton Athletic) wins a free kick in the attacking half.
Corner, Watford. Conceded by Tal Ben Haim.
Substitution, Watford. George Byers replaces Ikechi Anya.
Troy Deeney (Watford) wins a free kick in the defensive half.
Foul by Jordan Cousins (Charlton Athletic).
Offside, Watford. Daniel Tözsér tries a through ball, but Matej Vydra is caught offside.