Lucas Digne’s injury-time free-kick earned Everton a point and denied Watford what would have been a sweet victory over former manager Marco Silva.
Silva was sacked by Watford last season after an approach by Everton earlier in the campaign and the two clubs are still in dispute over the Portuguese boss.
And Watford were on the brink of a deserved three points until France full-back Digne stepped up to send a perfect free-kick beyond Watford goalkeeper Ben Foster with only seconds left.
Everton received the perfect start when another former Watford man, Richarlison, gave them an early lead – although the goal had a large slice of good fortune as Theo Walcott should have been given offside in the build-up.
Watford were a threat all night and they capped a fine start to the second half with a 63rd-minute leveller when Roberto Pereyra’s shot hit the post and rebounded in off Seamus Coleman.
They struck again two minutes later when the outstanding Abdoulaye Doucoure rose above Coleman at the far post to beat Jordan Pickford.
Everton were flat throughout, their display summed up when they were awarded a penalty moments after Doucoure’s goal when Christian Kabasele fouled Yerry Mina, only for Foster to save Gylfi Sigurdsson’s tame penalty.
Watford were holding on in relative comfort during six minutes of injury time until Digne’s crucial last-ditch intervention.
Watford so close to sweet victory
The sight of Watford players slumped on the turf as referee Kevin Friend blew the final whistle summed up the scale of their disappointment.
This game was played out against the backdrop of Silva’s eventual departure from Vicarage Road last season, which came after Watford warned off Everton in the strongest terms, after they had made an approach for the man who is now in charge at Goodison Park.
Watford’s travelling fans made their displeasure known throughout with Silva the target for some colourful abuse.
And their mood not improved when former striker Richarlison thumped a 15th-minute finish past Foster even though Walcott was clearly offside before Andre Gomes delivered the key pass.
The response of Javi Gracia’s side said much about their character as they were a constant threat against a lack-lustre Everton.
It was no surprise when they equalised and they looked to be defending their lead with few alarms, Sigurdsson’s penalty and a few scrambles apart, before Digne’s fine free-kick.
Watford look well organised under Gracia and Troy Deeney’s physical approach, as well as their ability to be first to so many second balls, took them to within seconds of a win few would have begrudged them.